[Ixnert]

With 700 under your belt, and a 15% ROI, you're very likely a winning player (close to 99%, if your 1/2/3 distribution is even). For answering that specific question, you don't need all that large of a sample (unless your ROI is close to zero).

As far as bankroll, $1000 will give you a sub-1% risk of ruin at the 22s if you don't withdraw. What I'd do if I were you is take $1000 of poker bankroll plus enough to take a relatively austere trip if you were to never play a hand. Then you can upgrade your plans on the fly according to your results -- if you're flexible, there's a lot you can do on the spur of the moment, as long as you're not looking to get into Broadway shows and the like. And if you decide you'd rather just enjoy the scenery, you have that option too.

Can't help you as far as wireless on the road, though; looked into that myself and never really found a satisfactory option if you're not going to be on/near interstates all the time.