[bushwickbill]

Hello, I'm a first year PhD student taking stereochemistry and I've been searching for a worthwhile modeling kit with no luck.  I need something to make accurate transition state models for determining product stereochemistry and the molymod kits the campus bookstore carries are insufficient.  I used a molecular visions kit in undergrad that was alright for making chairs but I still found to be lacking.  Something that won't cost an arm and a leg to ship to Canada would be great too.  Thanks in advance.

[Dan]

I need something to make accurate transition state models for determining product stereochemistry

This sounds like you might be asking a bit much of the humble model kit, depending on your definition of "accurate".

Anyway, some suggestions here:

http://www.chemicalforums.com/index.php?topic=33621

[curiouscat]

At some point, maybe software will win?

[orgopete]

For my money, I really liked the Molymod kit. Can another set give more accurate intermediates for transition states? This is simply my opinion, I'd be wary of trying to make that judgement. Look at all of the papers that one can find in which an alphabet soup of calculations are being made to determine which may better predict the outcome of a hypothetical transition state. Now the quest is to find a modeling kit that can supersede these calculations. That looks like a pretty big ask. I'd stick with the Molymod (and I really like that it uses bent bonds for double and triple bonds).

[Arkcon]

At some point, maybe software will win?

I'd say we're there already.  For advanced imaging like the OP wants, computer modelings are really more clear.