[Wine] most beneficial commercial wine software?

[bmaupin]

I'm sure the best way to support Wine is directly, through contributing code, money, or other resources.

but out of curiosity, if one were to purchase a third-party commercial solution, such as Crossover, Bordeaux, or whatever it is that Transgaming is offering these days, what would be the best choice in terms of contributing to Wine?  I guess what I'm asking is which of the wine-based commercial solutions contributes back to Wine in the most beneficial way, whether it be through code contributed back to the Wine code base, or through other means.