I've seen some things where the seller is definitely dodgy - telling signs like they have lots of great feedback but it's all items bought and not sold. I've seen an $8k camera advertised for $1200 and that just seems too good to be true.
But, the one you're looking at doesn't seem too bad - don't forget you might get stung for VAT by customs.
I recently bought an mp3 player from a seller in Detroit - in the UK they are/were £299 and I got it for £135, but had to buy a US to UK plug adaptor so about £150 all in, but still an absolute bargain.
Try to communicate with the seller and see what they're like and if you're spending a lot consider using escrow.com (and only escrow.com, not similar!)