Yeah me too -- I can't find out how to disable the notification disabler in Handcent anymore, so now DeskSMS is broken. I even re-registered push notifications for DeskSMS but to no avail.
I've had 2 OG Droids and have used my wife's OG Droid too... the keyboard on that had varied stiffness. My Droid 3 is very stiff too, but they do tend to loosen a little with regular use. Don't expect a lot, though.