For the $400 difference between the 3803 and 3805 I'd save the bills and run out and buy an spl meter and S&V disc...oh wait, I already did. The 3805 has marginally more power and more component inputs plus DPLIIx, but I think that's about it (outside of auto calibration of course). However, I believe you still have to purchase the optional mic to make the auto calibration work, so the price difference could actually be more than $400. If you need to have the latest and greatest, you know which one too buy. Otherwise, I doubt you'd be able to audibly hear any difference. The Yammie, btw is another sound choice. You can't really go wrong with either.

Good Luck