[G1 General] blueheeler:
Personally, I don't think the Hero builds compare with Cyanogen's Scary Experimental builds. I believe you sacrafice a lot of speed to gain very little (if any) functionality. Don't let the misnomer of "Scary Experimental" throw you off. His latest 3.5.3 blows everything else away. It's within a build or two of being declared stable. And most of the tiny little issues with 3.5.3 can usually be fixed with instructions being posted in that thread.

Moving over to Cyanogen's 3.5.3 is braindead simple too. Don't rush, follow the recommended upgrade path, and you'll be set. It does all the work for you, and it doesn't require the sometimes dreaded new SPL (which, BTW, is not nearly as risky as some will lead you to believe ... you just have to properly follow the required steps). Still, will this being your first attempt at any of this, you'll find it much less taxing on your nerves by sticking with a more straightforward upgrade. Cyanogen's is a great way to get your feet wet. And in the end, you'll end up with a blazing fast phone with all the bells and whistles too. Your phone will impress the moment it first boots. There are themes available now, and more will be coming once it hits stable. Apps2SD are automatically done for you if you have your sdcard formatted correctly. There are a myraid of ways to get the correct partitions on the sdcard, so do that before anything else. It will increase your chances of making this successful on the first attempt. Remember that a wipe is not necessarily a bad thing, it's usually that a failure to wipe is what caused your problem in the first place. Wipe if it's recommended. Read the comments to determine when it required, when it's just a recommendation, or when it's not necessary.

Be methodic. Since this is your 1st attempt at this, you'll be doing yourself a huge favor if you grab everything you need all at once. Don't try to take any shortcuts, follow the steps or instructions to the t. Make sure you have the latest radio installed (and the new SPL should you pick a build that requires it). Although they usually list the latest builds in the 1st post of a particular topic, occasionally they will release in intermediate fix within the thread itself. Check the last few 10 or so pages of comments for your build of choice to see what build is recommended at the time. Usually, you'll want to grab the latest build, but that's not always the case. Bleeding edge is not always best (althought with C's Scary Experimental, I've eagerly awaited each and every update because it's only gotten better each time).

Since you've done your research, go back and outline the entire upgrade path. Write it down for reference. Make sure your Windows driver are up-to-date, have the latest ADB installed on your computer (it makes things much easier if you use ADB if possible), don't do anything until you can devote a couple of uninterrupted hours to the upgrade process, and I cannot emphasize enough to WIPE as necessary. Hell, don't install any programs or fiddle with any settings. WIPE each step along the way until you get the final build installed. If something doesn't seem right any step along the way, don't proceed to the next step. WIPE again and re-flash. See if that fixes your problem. If it does, the proceed. If it doesn't, see if it's an issue that fixed with the next build you'll be flashing. If so, proceed. If not, look for another solution. Proceeding at that point _might_ be okay, just be aware that you might get yourself into a situation that requires re-rooting your phone.

Make sure that before you do anything else that you have one of the modified recovery images flashed to your phone. They're modified for a good reason.

If things go bad, don't panic and start posting that you've "bricked" your phone. Chances are you haven't. Very few phones get "bricked" to a point you can't fix it yourself. When people around here see the term "bricked" as a subject in a post's topic, it's a red flag that becomes a red herring for you. You may get into a boot loop or something, but it's usually fixable with a WIPE and an update.

Also, keep DREAIMG.img in the root of your sdcard at all times. Don't move it, don't delete it, don't rename it. It can, and will, save your ass if any of this hits the crapper. Carry it with you at all times. If you have DREAIMG in the root directory, you'll always be able to get your phone back to an operating condition, wherever you are, whenever you might need it, without the need for a computer. Yes, it would be starting all over again, but it would give your phone basic functionality if all goes to hell and you're not near a computer or don't have a USB cable or something.

None of this requires a PH.D. It's actually quiet simple. Most people that run into problems have simply missed or skipped a step, or failed to wipe as required. Knowing recovery proceeds in advance will be helpful, but even that is pretty straightforward and easy to follow. I've done all these flashings, re-flashings, recoveries, etc., so much that I --think-- I have the terminal commands etched in my memory. And I do. But I still refer to the on-screen steps to make 100% sure I'm typing things correct. I hit enter only after I'm confident I didn't type a 0 when it should be O (hehe). I look at the screens during the whole process for indications of success or failure. And I make sure that I am not distracted by anything when I upgrade. Lock yourself in a room by yourself after you've emptied your bladder. If you do get interrupted or have to take a bathroom break, write down the next step. Don't assume you'll remember. And don't even think of making or taking phone calls until you've finished this whole thing.

Read in advance.

Search as necessary.

Ask, in the appropriate forum and thread, when all else fails.

You'll do fine.

Good luck.