I've shot the XDM.45, and I like it.
Haven't shot that particular Ruger but have shot the SR9 and SR9c, their autos these days seem really solid.
Between the two, the Ruger is a bit shorter and lighter unloaded. But you give up some capacity.
Tough decision between the two, would come down to which was more comfortable to me. XDM will be more supported in the aftermarket, I like the looks of the Ruger better.
Looking outside of those two just for sh*ts and giggles....
More $ but I have my eye on this .45: http://www.kimberamerica.com/product...y/ultratle_II/
I shot this HK .45 a few weeks ago at my camp, my buddy just bought it and this was its first run, it was impressive but again is more $: http://www.hk-usa.com/military_produ...45_general.asp It was really freakin accurate.