I may be mistaken however I think that the 810 has all 3. I've only used the 810.
I use the "thumb" board while I'm walking.
I use the little "hunt an peck" with the stylus, especially if I have to enter numbers.
I slide out the keyboard fairly frequently if I need to do more than a few words.
I hook up my $30 BT iGo when it gets serious.
The thumb board is good but you have to shift for numbers etc. The h&p is very handy for phone numbers etc, (no double tap of the Fn key).