If you're looking into 61/2 and 6x9s and you're eye is on the infinitys then I'd say your budget is in the $200-250 range for 2 sets of speakers. The kappas are very nice sounding speakers for thier respective price range. Midbass wise out of the components can be a little finnicky so installation and sound deadening will have to be top notch. Tweets on the comps are bright but bearable unlike the perfects... *ouch*
ANother similar brand which IMO sound a bit better with a bit more midbass punch would be the ALpine TypeR component sets and 6x9s.. If you search on ebay you can get some great prices around the same price for the kappas.
Lastly when people are in the entry-mid level budget range for speakers, I haveto always suggest the Rainbow Dreamline comp set and if you want to match..their 6x9s as well... decent midbass punch but very very smooth tweet. Try ampmanaudio.com for these..
I hope this helps
