I'm still looking at the 8525. I have small hands, BUT need glasses or contacts, and I do send a lot of emails. The wide screen and full keyboard might help. We will see. You know me, I try almost everything, LOL!
Take this with a huge teaspoon of salt, but I just tried, and returned, the 8525 that AT&T had on the $99 sale two weeks ago. I am back to my Blackjack again and much happier. The 8525 is a nice PDA, with a spacious keyboard, but it just was not a convenient Phone/PDA. Maybe I'm just spoiled by the smallness of the Blackjack, but it's also an interface thing. The Blackjack has become a great one-handed device when you blend the jog dial/launcher, and keyboard. I always felt like I was fumbling for the stylus to do anything on the 8525.
What I missed above all was from the home screen simply typing the first few letter of a name and up popped the correct contact list to call. No need to launch contacts and type or scroll for a name. Granted, the 8525 was snappier than the Blackjack (can't beat that 400mhz processor) and web pages looked better on the larger screen; but 3G was equally as fast on the Blackjack. After a couple of days,I found myself swapping the SIM card back to the Blackjack for good lengths of time and then swapping back to force myself to give the 8525 a chance.
If you really like the 8125, you'll love the 8525; but I'll take the Blackjack any day. Sorry for the OT rant.