that is probably the best deal you're going to find.
sites like pricegrabber.com, shopper.com, or mysimon.com seem to show prices of 410 + shipping.
and i've also been in the market for the s30 and 420 is the lowest i've seen. keep in mind, the shops selling them for the lowest price are usually the shadyess ones. seriously, i've had nothing but trouble with them. (don't make me start ranting . . . i could go on) basically they won't sell to you unless you pay $$$$ for extras. they'll lie and deceive you. so the best alternative is to pricematch with an american express blue card. (you'll find tons of information about this card online) as far as i know, most BM stores will not pricematch online retailers either . . . which is another benefit of the blue card.
sorry to be so vague, but these topics have been covered extensively on the topics. just hunt around.
-keymo