[Asus  Eee Pad Transformer Prime] deadwolfbones:
My first impressions:

NOTE: My only previous Android tablet was a Nook Color w/ CM7–Phiremod.

NOTE: All impressions are regarding the stock launcher unless otherwise noted.

1. Overall speed/smoothness/stability: Very Good

The only time I've noticed any real slowdown with the tablet was when I was initially downloading all of my apps as it sync'd to my market account. Things got a bit frustrating for a few moments there, but as soon as it was done trying to shove a ton of data down a small pipe it was fine. (Later I realized I had the ASUS performance governor on the economy setting—I suspect it would have been a lot smoother with it on "balanced" or "normal" settings.) Paging between launcher screens is usually very smooth, and opening the app drawer and paging through the apps has very little to no lag for me. What little hesitations it does have seem to disappear when I switch over to ADW Launcher EX, but I haven't fully customized that launcher yet. Games run smooth as silk on the "normal" performance setting, but I find balanced and economy to be just fine for pretty much anything else.

(The tablet did a "hot reboot" once—immediately returned to the chromed ASUS logo and then back to the homescreen. Shortly after that I got the firmware update and it hasn't happened since.)

2. Wifi range/stability: Great

No issues here. As I noted in another thread, the signal strength on my Prime is significantly better than it is on my Droid Charge (-50dBm vs -70dBm in the same spot). It's never dropped the wifi connection and I can get a signal in every corner of my house and even out in the front and back yard (yes, I waded out in the snow to check it). I haven't tried Bluetooth range/stability yet, but I'll update if I do.

3. Battery life: N/A

Too early to judge this one, really. I charged it fully (but nowhere near the suggested 8 hours) before really digging into it, and then played with it for about 6 hours straight last night before putting it to sleep for the night. Wifi on, auto brightness, playing YT videos, loading webpages, downloading apps, etc. Mixed between "economy" and "balanced" performance settings. This morning it had 38% left. For a first charge I think this is pretty good, as it usually takes me a few charge cycles to get max battery life (and I didn't follow the manual re: initial charge on this one).

4. Audio quality: Average

Single speaker, not overbearingly loud, and no bass. On some sites and in some programs, with the volume cranked all the way up, it was just barely intelligible over the sound of my (mid-volume) TV. On other sites and other videos, it was quite loud. At full loudness it distorts a bit at high frequencies, but I've yet to find a tablet speaker that doesn't. YouTube videos seemed a lot louder than other sources, for whatever reason. On the whole, I'd say the sound compares favorably with my gf's 1st gen iPad, which isn't really saying much good or bad.

5. Build quality: Great

No issues whatsoever with the quality of the build. No creaking, no flexing. Quality materials and tight assembly. The industrial design is nice and understated; the sharp edges take some getting used to, and I have to say I'm not entirely sold on the 16:9 ratio from an ergonomic standpoint, but it's easy to hold and use overall. The screen is superb—great color rendition, sharp, and no backlight bleed that I can see so far. When I was initially setting up the device I did have a vertical column of staticky multicolored pixels down the right side, but once it got to the homescreen these disappeared and I haven't seen them again. The glass is a bit more reflective than I'd like, but I haven't seen a single tablet that's any better, so whatever.

6. Other notes:

Browser: Switched from the default to Opera Mobile and so far I'm liking it a lot. I tried a bunch (Firefox Beta, Dolphin HD, etc) and Opera had the smoothest scrolling and fastest overall performance of the bunch. Dolphin was close, and I prefer its tab implementation, but ergonomically it was second fiddle for me.

Keyboard: Using Tablet Keyboard at the moment and it's serving its purpose a lot better than the stock ASUS or Honeycomb keyboards. I will give SwiftKey Tablet X a try this evening as I use and love the phone version.

Launcher: I really wish there were more alternative HC launchers available, but I think that's more my obsessive need to tweak things speaking than any real fault in the stock HC launcher. For most purposes it's a-OK.

If anyone has any questions I'll be happy to answer them. On the whole I think this is a fantastic device.