I have 2 Sparcs, one I mess around with on an AK and the other I keep as a spare red dot. They are great bang for the buck and the customer service is always good. Hard to beat unconditional lifetime warranty.
The Sparc has 3 flaws IMO: 1) is the tinted class, it's not a big deal, my Trijicon reflex has tinted glass and you get used to it, but I like the Bushnell TRS25 is that regard the glass isn't tinted as much. 2) When the battery starts going dead, the dot does weird things, some shots it works, other shots it turns off. It would be nice for a "dead means dead" feature. 3) if you bought one of the old Sparcs on sale since the Sparc 2 is coming out, the originals use bastard batteries, they're 2354s and cost 4 bucks a pop. The Sparc 2s use 2032, plus they come with small flip up covers instead of the rubber bikini. But I don't bother to put the bikini on either one of my Sparcs so..
It's nice that they use an Aimpoint Micro mount so if you want to get a QD mount from LaRue or American Defense they pop right on, or just get an aftermarket mount from Seekins or Fortis.