I own an OG Timmy and the Timmy v3, probably my favorite OD pedal. They can be dialed in to sound pretty much exactly the same. Timmy v3 has more gain on tap via the switch, Paul Cochrane said it's supposed to bring the Timmy into the gain range of the Tim. Biggest difference to me is the taper and direction you turn the bass/treble knobs. On the original Timmy, max bass/treble is fully CCW. Timmy v3, max bass/treble is fully CW.
No experience with the Tommy's, though I have a Tommy III that I'll be assembling soon. I fully expect it to sound identical but I can report back.