Wait until some of the true audiophiles get on here, they'll give you both the technical reasons and the audible ways to determine the "best" speaker.
HIGH end brands like MB Quartz, Blaupunkt, etc sound awesome. (Personally, i have Blaupunkt 6x9 4-ways with crossovers in each door., though I'd dump those for some MB's!
Dnewma04 is into audio alot, as well as a few others.. they will help you define the terms to look for as soon as they see this post.
