A 150w would be better than 2x125 CFL's.... Let alone a 250w HPS.
I've found that all the talk of "CFL's give off less heat" is b/s for the most part. It's really not that much more watt v watt, but what is a huge difference watt v watt is the lumens.
Go HPS all day. Perhaps buy a 150w, and if heat isn't a big problem, then buy another. Two 150w HPS would be about the same price as 250w HPS... So a good deal.