Ill add my vote for a switch as well (who wouldnt on an EVO forum!!
)
Now for some actual details for you.
I came from a long term TREO user. Every Treo sprint carried from the 600 on, I used for some amount of time. (up to the treo 800...only skipped the PRO) I was always addicted to the keyboard and leery of leaving it behind. I took baby steps and jumped to the TouchPro 2 for a year after the Treo 800w. It too had a full keyboard, but also a soft keyboard so I could "get my feet wet"
At the same time I switched from a BB 8830 to a Storm on my work device. After the lackluster Storm experience and a so-so experience with the soft keyboard on the TP2, I was VERY worried about your exact issue. The softkeyboard on the EVO is great. I routinely do full emails on it with no issues.
Having used a coworkers EPIC I do have to admit that the display is beautiful, but otherwise I was not impressed, and even though it is much closer in design to my beloved TP2, I was not tempted to change at all.
As far as reboots, like any phone you will reboot occasionally, but its NOT as common as with the BB and much faster. BB reboots are usually measured in MINUTES (3-4) but the EVO reboots in about a minute if that long.