Geissele is the almost the only real option for a tactical AR. Go with the SSA and you won't regret it as you won't have to keep "upgrading" your trigger
I have a Geissele Match DMR trigger on my mk12. It feels better than my SSA trigger, but the SSA feels better than all other triggers out there. Can't go wrong with anything by Geissele.
^^^Geissele is hard to beat.... if you are building on a budget, check out Bill Springfield (triggerwork.net). Put his trigger in my MA-Ten build, and it is smooth, crisp single stage.
I recently purchased a DPMS SASS which uses an adjustable JP trigger unit. The only other aftermarket AR trigger I have messed with was a Jard. The Jard was great, but this JP unit is really smooth...
I run a SSA-E in my MK12. I haven't tried the hi-speed at all, just don't have the need for an adjustable trigger personally in my ARs, but I don't shoot hi-power either.