love, love, LOVE my 60% board. never have to move my hands from the homerow for anything, especially with my caps lock converted into an fn key on my pok3r... so nice.
i use a full-size when i need a number pad for homework and for when i'm using my desktop computer, but i generally find myself swapping it out for my pok3r, anyway. i should also note that, as an accounting student, i dislike using the numbers above the alphas and prefer having a number pad for ANY sort of number data entry, even if it means i have to move my right hand off of the home row (which seems contradictory given the following), but i find that the utility and efficiency i get out of a number pad far outweighs the convenience of a number row above my fingers (which isn't even that convenient - i never learned to touch type the number row and i find it useless given the general availability of a number pad when i need one). when i figure out the wiring and find a place to cut the plate, i'm planning on converting the number pad on my aek ii into an external numpad so i have one that i can use with my pok3r - screw the navigation cluster!
i also find myself trying to use caps lock + i, j, k, l on my full-size board, and then sigh heavily when i realize i have to take my hand off of my keys to use the dedicated keys. i don't think i could live with a tkl... it just seems pointless when all the functions are available and in a much more ergonomic package in a 60%.