Re: should i buy floor model tube amps?
Warranty is from the date of Purchase by the customer, should be a minimum of 1 year for electrical goods.
The only exceptions are when manufacturers provide exptended warranty, such as boss pedals, where the warranty is from the date the DEALER purchased the item. If the item has never been sold by the shop, it'll will have at least a full year's warranty. Just make sure you register, Peavey stuff requires that I believe.
When my shop (which Nick^^ may have been to...?) sells an amp we're always willing to discuss price. Because our shop's quite small, and all the stock we hold we have to put out particularly with amps, we have to sell the floor model. We wouldn't expect someone to come in, ask for say, a Blackstar series one 100 head, and then we go 'ok, to ensure you get a brand new boxed one, you can't demo it, you just have to buy it', lol. Nobody's generally trying to screw anybody, but we have to let people try amps, and we also have to make money, so we can;t just hack a load off the price : ).
EDIT Don't know about the Peavey registration thing as a fact, as my shop doesn't sell Peavey. When I bought my 6505+, it came with the warranty card where you write your details and had a prepaid postcard thingy (to use the technical term).