I'm using it.
I recently got my Treo Pro from ebay. Very good cell phone with many tweaks available, and it's kinda unique here in Brazil. Considering that this phone used to cost nealy US$ 600, to get one for 10% of the original price is great.
Its features are still useful and sometimes up to date.Recently I had an iPhone 4 (overrated), a Lumia 710 (still got it - love the phone), a LG Cookie GT 350 (lack of WiFi kinda killed the phone, but had a great design and eye catch colors), and more recently a gave my Motorola Razr i to my girlfriend. She loves it. Very good phone for a cheap price.
Still, the best of all is the Palm Treo Pro - got it syncing to my windows 8 (email, pictures and videos, musics, documents, etc) using the Windows Mobile Device Center - had to do a bit labor before get the sync to work properly, but now it's all good.
The keyboard is just a bit tricky at start, but you get used to it, and hardware keyboard and buttons are a must have features now for me in any phone. WiFi button is cool, silent switch is great, and the possibility of tweaking the phone system makes it a one of its kind nowadays.
Great quality of calls and music overall, tho my audio jack complains a bit depending on the way i put the headphones on it.
I'm Very happy with the Palm Treo Pro.