Not bad, a little lighter than XT(600g front and rear) - looks like 355g - 95g for disc for 260g a side(520g total)
More than anything, the price is great...how good are they...anybody want to post how they like them?
I've used both the XTs and the Hayes fairly extensively.
Honestly, they are both about equal as far as performance imo. Where the Shimanos shine is their ease of maintenance and set-up, but if you're wanting the lightest you can get.. and don't mind dialing in your brakes maybe a bit more, the Strokers are pretty awesome. Especially at such a good price. If I needed brakes, I'd prob jump on this deal.
That said, I'm a bit of a weight weenie so take that into consideration.