well what kinda wah tone are you after? Kirk Hammet? :lol:
nah kidding.
Give us what kinda music you play, budget, gear like guitar and amp used, and what kinda sound you hope to achieve before we toss you the recommendations...after all to me, wahs are very personal tastes....its like someone may feel the taste durian is heaven and for another, well urgh....
EDIT: ok i saw you've gt a budget of 150. which kinda limits your choices to only the Vox and Crybaby variety...and the higher end crybabies are out of the picture. Your best bet is to hunt down one secondhand.