I'm looking into purchasing an Eclipse touch screen head unit. For me, it's a toss-up between the AVX2494 (20GB Hard Drive built-in) and the AVN5500. Looking for personal experience with either or first-hand knowledge. Questions: Is it worth the price, are they quality head units, and if I can purchase one cheap but without a warranty (still get professionally installed), should I do so? (To be used in dash of '01 Explorer Sport.)