Brass or Bronze Valve Guides?

I'm gonna rebuild my heads but on Ebay i cam across thease http://cgi.ebay.com/ebaymotors/LOT-MITSU-3000GT-DOHC-BRONZE-VALVE-VALVES-GUIDES_W0QQcmdZViewItemQQcategoryZ33617QQitemZ8023 254842QQrdZ1QQsspagenameZWD1V as oppose to 3sx's brass guides. The ebay ones are a little more expensive but is there really a diffrence? Or should i just trust the 3sx ones more?

I don't see why they would make a difference... Bronze should last longer but probably not enought to justify a cost difference with a rebuilt engine.

I don't know...but consider this

3sx deals 100% with our cars
ebay deals 95% with complete crap