If you enroll in
Zwiftpower, after any group ride or race you can see the detailed stats of yourself and any other riders in that ride or race who are on Zwiftpower (it is free.) You'll see max watts and W/kg, other info.
I love big rides like TdZ where you can ride at the pace you want to ride up and almost always join a group going at the pace or just slightly above/below. I don't really care about how many watts the others are putting out - just nice to be able to sit in draft and rack up more miles in a one hour ride at the pace I would have ridden solo with no draft. With distance rides (vs set time period), like TdZ, I try to latch on to a slightly faster group so that I'm doing close to the same power I was solo but going faster because of the draft.