About Triton 2+ and 3+

A few questions, any feedback would help me at this point

I'm looking for a pair of Goldenear Triton 2+ or 3+ (which would be better in a 20 x 20 room, is bigger better?)
My thinking is that buying used would be OK because audiophiles are more likely to take good care of them?
Assuming I went with used, where's the best place to look for them?

Thanks - rev