Mixing mods

[Mimesis]

There seems to be a ton of interesting mods for Minecraft but I'm not sure how well they work together. Let's say I wanted to have Thaumcraft and the Chocolate Quest mod, would one mod likely negate the changes from the other?
After seeing some of the mods I'm considering buying the game to try this out but it would be nice to know if combos generally work or not beforhand. Perhaps someone's got some experience with this?

[PizzaSHARK]

Quickest method of checking is to run both mods and read the crash report if Minecraft crashes. After the initial list of crap it was trying to load it'll tell you why it crashed. Otherwise, download both mods and see if they both try to modify the same .class files; if they do, they're incompatible unless someone makes a patch like Better than BuildCraft for BC+BTW.