I just got one of those flexible keyboards. They're not too bad to type on. Not as good as a REAL full size keyboard, not quite as good as the KB on my Mobilepro 780. But better, I think than the integrated keyboard if you are going to be doing a lot of typing. Long emails or a lot of terminal work...
(Even though I think the integrated KB really isn't that bad at all...)
The build quality is pretty good (now let's see how long this thing lasts in my messanger bag as I tromp across Japan...), and it was recognized fairly easily (seems like it has to be connected when you power on the unit...). The keys don't seem too unforgiving. Leastwise I didn't feel as if I had to MASH them or anything, just typed normally.
One thing I DO NOT like is that for some odd reason it has two 'enter' keys right next to each other. One is the size of a letter key, the other is oversized (verticaly). A weird design IMHO. Weirder still, it has two letter sized shift keys on each side instead of one double sized key, again right next to each other. Same surface area, but I don't like mashin' around on the edges of keys, even if they are soft and still work it just feels wrong.
Maybe it's like that to preserve flexibility, I don't know...
Overall for $16 (shipped) I suppose I'm happy with it, but it does have it's faults.
I had the Pocketop IR keyboard before with my 5500, and I like this flexi one much better already...
Just my opinion...