While the offset iron sight concept seems to be gaining traction, there still aren’t more than a handful of manufacturers that are actually producing them. I just learned of a fairly recent addition to that short list from Harris Tactical. The GG&G 45 Degree Transition Sights look like they split the middle between some of the offset iron sight sets that are currently available. They offer more precision than something like the XS Sights XTI but lack all the adjustment at the rear sight like the Dueck Defense RTS (which some users may not need).
Check out the GG&G 45 Degree Transition Sights at HarrisTactical.com.