727 Rebuild!

Im currently thinking of rebuilding my trans this winter!
I have been looking around for rebuild kits but i dont really know what to go for! My car sees alot of street and also sees strip use!

Ive been looking at Hughes performance rebuild kits and those offered with Kolene steels. Link to kit
What should i go for? This is a street car that want a stout 727. What else should be exchanged than those things that come with a rebuild kit? Or is the rebuild kit enough?

How much differnce does an aftermarket manual/automatic valvebody do? I dont want a manual vb as it sees more street than strip. But does aftermarket vb:s do much differnce to shifting?

My engine has been dynod to 420hp.

Cheers!
Chris