[Advantage X7500, MDA Ameo General] fortissimo:
May be the OP wants to clarify if he really wishes to compare UMPC to Athena or the more comparable MID vs Athena?

One poster said UMPC has "rubbish battery life" which is only true, but it is because those UMPC was yesterday designed, and not many newer UMPC have been built.

UMPC is defined as Ultra Mobile PC, which is coined by Microsoft, so mostly it is used to described Windows XP Tablet Edition OS devices. Similar form factor devices are appearing on the market again, but they are simply called tablets.

What Athena should be compared to, because of similar form factor, should be MID, which stands for Mobile Internet Device. MID can run Windows XP, or Linux, or other systems, and doesn't have a platform specific thing.

For example, my Samsung Q1 is an UMPC, and it has a 7" screen. For example, my BenQ S6 is a MID, and it has a 4.8" screen. One runs XP Tablet Edition (factory) and one runs XP Home (factory). My Q1 has only a 2 hour battery life (now only 1 hour as the battery wore out) w/ a 3 cell (factory) battery. My S6 has a 4 - 6 hour battery, while having a much smaller Li-poly battery pack, with much less capacity than the one inside the Q1. So you can see, it is not a fair comparison when you compare UMPC vs Athena and compare MID vs Athena.

I own all 3 types.

Fast and slow are all relative, I tell you.

WM can wake up in a flash, so you call it fast. But then if you want to play a high quality video, or Adobe Flash, it just doesn't have enough processing power, then you call it slow. Let's define what you mean by fast and slow.

Windows XP takes forever to boot, so you call it slow. But most modern device, including the lowly Atom CPU, even the low end Z series, can at least play some Flash videos without a lot of problems. So you call that fast? So what is true? Is it fast or slow?

The Atom Z series platform (in various netbooks and MIDs), can do standby to on in very quick time (about 2 sec). It is also very good on battery life, with very low power consumption, especially in idle or standby. That's why I wish the OP was trying to compare MID to Athena, because UMPC is just an orphaned platform without any new entries lately, and thus is a very poor case for going to battle here.

I disagree that the Athena "has crazy battery life" if you meant "great". When I had it on with 3G enabled, it didn't really last very long. Worst if you have Push enabled, or even pull (either way). I did read about the ROM making a diff. but in the earlier days, all I used was factory ROM, so there is nobody else to blame if that's the case.

I do agree with vma in general. I now use an iPhone for my daily phone, and I own 2 netbooks, with 1 having a 6 cell battery. They are the bread and butter of my assortment of equipments at my disposal (which is a lot), which I use the most in a real portable / mobile situation. iPhone as a daily phone and data device, while netbooks being used in meetings / gatherings etc.

I also will take out my Athena or my MID (S6) just to fill the gap, if the situation requires, but this gap is like a niche, so they don't get used very often because of that. For example, if I have to walk more than drive, and thus don't want to carry even a netbook, but at the same time I really need to have Windows (native, remote won't cut it case), then I have no choice but to carry the MID w/ XP (S6). But that doesn't really happen too often. More and more apps are available on iPhone that slowly replaced even some of the very niche apps on Windows.

Athena is worse, there is even less niche that I must have WM w/ me nowadays. Most apps have been replaced, and fewer required. For example, having a connected Garmin Mobile XT is nice, but I already own a GPS nav plus software on my iPhone, so I need WM even less even it does give me that combo, but it is not absolutely necessary. It is just nice to have (an also do case).

The saving grace of the Athena is SkyFire and Opera Mini 5 (compiled binary version especially), and latest cooked ROM on 6.5.x. Otherwise, the Athena is really outdated. Many apps are already duplicated and I can't think of any that still remains a huge advantage (no pun intended) on the Athena, except one (which is a niche app, most people don't need / use it, as it caters to only certain kind of people).

With all that said, Athena still has one slight advantage (no pun intended), and that is if you have a pretty stable environment / system, you don't really have to worry about maintenance down the road unless you add / subtract things from it. If it is stable, it should remain so, as the system doesn't get much changes, unlike XP which has constant security problems and thus updates and this and that. iPhone being a very fluid environment only because there are a lot of new updates which are either essential in order to have some new highly anticipated features (hard to ignore), and then apps compatibility afterwards. With Athena, if you can tolerate not having new ROMs or apps, and use it as a stable appliance, and you can actually achieve a stable env to begin with (not always the case, WM is not that stable, the more apps you install, the less stable it becomes), then it is rather reliable. Look at CE Embedded, many GPS nav platforms use that as the base core OS and it's stable. It's only unknown apps can affect it.

I can maintain my XP well, but it takes efforts etc. I also maintain my iPhone from time to time, but not as often, but each updates is a new battle to test everything once over again, lots of time and stuff. For Athena, it used to be like that, but now since one should find a stable ROM and be content with, then it's ok. But that may be because there aren't any new killer apps out there, that demands the newer versions of ROM / OS version, so it is no longer an issue.

But it doesn't necessary make it easy though. I struggled to make Athena stable and for the longest time, WM is very hard to tame (worst of all handheld platforms IMHO!).

I'd say, if you are very good in maintaining Windows (like XP), an XP based MID is actually a very good choice today, with the new Atom Z (or even N) series CPU. You just can't expect it to be a phone for voice stuff (even if so, I can't trust XP to be 100% reliable in voice handling), as a data only device. And that can replace Athena as a similiar size platform.

For example, my S6 is about the same size as the Athena except longer (should say wider, but the longest side), if Athena is in its leather case w/ keyboard. However, I can strip down my Athena w/o keyboard and leather case, and it becomes very thin, (and no protection), but I can't strip down my S6 any further. It is also hotter if run long also.

As for UMPC, I don't know if XP will be able to compete still, as there are surprising few new models as compared to Linux / Android based ones coming out these day. I found Vista very unsuitable (for just about anything) and even Windows 7 doesn't provide the efficiency like XP can (battery life, graphics performance), and only provide a bit more convenience, but tax a lot more resources that is not worth it in a low power, low resource small device. Leave the W7 to more powerful computers.

It all comes down to what apps you need to run. If you have apps that only is avail on one platform, you probably don't have a choice. If you only need popular apps that are avail on all platforms, then you have lots of choices and lots of debates.

But one thing is sure: if you need powerful stuff, even some video playback, just don't kid yourself, the Athena can't cut it, I tried pretty much everything. Even the Z500 + GMA500, considered the lowest end on an Intel based platform, will beat the Athena playing videos. Browsing is the same also. There is just so much an ARM based CPU can do, especially without modern GPU on the side (The ATi chip is really not helping much in the Athena, despite the brand behind it).

If I have to choose today, I'd take iPhone + netbook like vma said. But if I have other needs, then I'd take iPhone + MID, or iPhone + UMPC. My WM devices are now niche devices today, changed their roles from their past, no longer the centre.