I have 3 Pre3s(1 French or German I forget, one UK and one US ATT). I only use the ATT one (frequency support). It's been my main phone since I got it in March of last year, before that I was on the EU Pre3s for several months and they worked OK too minus the HSPA(?) and full 3G frequency support for ATT. I even switched off of Sprint onto ATT to use the Pre3.
I have 3 Touchpads(bought 5 during the fire sale, have two of those left plus the one I bought on the day it was released). I use one daily as a basic web browser, mainly browsing the daily pictures at izismile.com before I goto sleep. Java script is kept off unless absolutely needed, same with flash. The only 3rd party app I use is "WebOS news", I've bought tons of apps/games back before things got canned but lost interest in pretty much all of them by now. Other than that I watch some video on it, few times a year I use it for music...
My last touchpad is still in the brown box HP shipped it to me in. Never been opened. Don't really have a use for it right now other than a spare, and it has more value to me personally than it does market value so I don't intend to sell it. The other touchpads I gave 2 away for Xmas in 2011 to family, and sold a 3rd to a HP employee who could not manage to get one(sold at cost).
How long I can last, I'm not sure, in theory I could last probably as long as 3G frequencies are still around and I have batteries to run my phones. After WebOS had it's throat slit I bought a GSM Pre2, and when I signed up for ATT I got a "free" Veer as well. So I have 5 webOS GSM phones, 4 of which have hardly any use at this point, and the 5th one(my current phone) still running strong. Buying all that wasn't cheap, the costs were huge, and it was a tough decision to make.
I do like the look and feel of the Samsung Galaxy Note 2 with the ultra big screen (I have big hands), though I don't trust Android because of Google. So I can't use it. Not a fan of Apple either, so iOS is out. My company gave me an iPad mini for xmas and I had it sold to a friend before I even had it in my hands. That guy told me something along the lines of "lots of people say they wouldn't use something even if it was free, but not many go through with it!"
BB10 looks interesting, I could see myself using that -- more so if it was in a Galaxy note 2 form factor. The slide out keyboard is nice on the Pre3 though it is still somewhat difficult to type with my big fingers(more like edges of fingernails really my thumb takes up a bit more than a 3rd of the KB on the Pre3).
I have a friend who is an MS employee who has windows phone (his GF has one too she too is an MS employee) - neither are enthusiastic about it. There are some good things, some bad things. Nothing to write home about.
I feel the same way about WebOS - I've never promoted it to my friends or family - it always felt it needed more work - it had (perhaps still has) promise, I could see the vision, but it was about maybe $4B short of what they needed in order to pull it off.
I haven't spent more than a few minutes using any Android device, and even less time using an iOS device, so I really don't know what I'm missing I guess - ignorance is bliss.
Also in case it helps understand me - I've been using Linux as my desktop since 1998, so I'm sort of used to being a spare tire in terms of what is supported.