I haven't had a chance to compare a 3 with a 7-35 yet, but the XRS2 was *very* close to my eyeballs, and the 3 is a noticeable improvement.
If anyone wants to see an XRS3 in person, I will be RO'ing the Kestrel Fall Classic at Altus this weekend, but my match rifle (with XRS3) will be with me.