i bought one 2 years ago when i took orgo my sophomore year, and i never even unwrapped it. It costed me bout 40 bucks and I ended up reselling it after i finished taking orgo. I think i only needed it about once, and I ended up using my study buddies orgo set which he got alot cheaper on ebay and was much cooler than my set. It was one of hte prentice hall model sets.