WWE used two different piston makers: Arias & CP. Both are good manufactures with decent products, BUT WWE weakened the design by doing his own machining to the pistons after they were produced. One mod included a drilled out piston pin (dangerous).
JE pistons makes a good product, EXCEPT for the custom built pistons they made for us Cannondale riders thru Special Order requests. These are junk. They do not last and will cause problems long term.
Wiseco made a couple piston designs for us (stock non-custom designs) The big bore 450 piston was a Wiseco design. They do not last but about 15 hours or less and the skirts start to shrink in and cause smoking and compression loss.
CP pistons in the custom designs pioneered by Timbo of this site are the preferred pistons for long time use and performance. They took all of the issues we had with previous designs and made us a well built piston.
Any custom piston kit will set you back $400 plus with the sleeve kit at todays prices. The ASSO piston kit with sleeve and all is just $150 from Black Widow or Dave. If you want to go large you have to pay. The leftovers you will find out there (WWE, Wiseco, JE) are just not worth the time and the money due to their issues.
You don't want to spend the extra money? I am positive I can find you a set of at least regular rings for that POS WWE piston kit. You will be back when it implodes. (see destruction thread for pics).
The ASSO 432 kit is! My Z400 bearing is on its way in, and the head soon from porting. With any luck the rest of my shopping list (including the piston and liner!) will arrive within another week and I can start the assembly. Lots of thanks to all who chimed in with great advice and ideas. I'll be reporting back as soon as I have the engine together or if I run into any problems 