Hi i currently have the little mark 3, which runs 4ohm 500 watts, or 300 at 8 ohms, and was just wondering which version of the traveler 102p to run with it, is its either the 8ohm at 400w or 4ohm at 400w?
You probably won't be able to put the full 300w into the cab before it farts out any way, so I would recommend the 8 ohm version which will allow you to add another 8 ohm cab (maybe another 102P) for when a single 210 isn't loud enough.
I'd go with the 8ohm, gives you more options later. I run a single MB NY151 (8ohm) with an LMIII and I never come close to maxing it out. Seriously, 1/4 volume is enough for most of my bar gigs without PA support.