Hello. Welcome to PPRuNe.
Great resource for newbie/wannabe pilots, rotary inclusive. The 'stickies' are there for a reason. Especially
http://www.pprune.org/search.php this function when logged in.
As for my personal opinion, I find Bristow Academy bit premium for Americans who don't need JAA (European) papers or J1 visa (still for short while). There is definitely mainly positive feedback about the school itself. But then, any rotary training is going to be expensive.
Do learn about SFAR73 and R22, since it's most common 'trainer' chopper and how having most of time in S300 would affect it. Also count with 200h TT rotary to be able to instruct in R22 in the US. Also the amount of time in R22 and say, at least 25 in R44 for greater chances in tough new CPL(H) market. Etc etc.
You can spend literally months researching various schools, smaller to bigger, pros and cons etc.