Here is an answer regarding sights from a review of the XD-E:
And from a discussion on a Springfield forum:Springfield Armory XD-E sights are compatible with the current XD dovetail dimensions (which are, entirely uncoincidentally, the same as the classic SIG Sauer P-series.)
I went with AmeriGlo on mine. Any of their XD/SIG sights work except for one XD one that's model specific for I think a .45 in 5" and the SIG #6. They're clearly labeled though so as long as it says XD, SIG #8, or SIG they'll work.