is this a good price for W2's/will it work for my combo

hey guys,

im eyeing a set of assembled W2 heads that are brand new for 850 bucks...the part number is P5007089 and they are 55cc chambers with 2.02 int and 1.60 exh valves...just wondering if these heads would work with my 340 which has flat top pistons (as far as i know, and currently running closed chamber x heads) and 10.5:1 compression....i dont plan on putting them on right away, but i was thinking of grabbing them since the deal seems pretty good...what do you guys think? are they worth it? would they work with my combo? i have no idea what the 55cc chambers mean for performance, so any help would be great!

THanks!
Matthew