Read a lot of posts comparing scopes and it is like the proverbial drinking from a fire-hose, so much info I can't distill it down to an answer.  Figure may as well ask the specific question.

I am looking for a new scope to initially be switched between an AR-15 and an AR-10 for range work primarily.  It may ultimately end up on one of those guns or a 6.5 (grendel or creedmore, still debating) or my .308 bolt gun that currently has a Vortex Viper PST 6-24 SFP.  Looking for something with upper magnification in the mid-high teens that is fairly compact and light.  I would prefer a FFP with a milling reticule.  I don't think I need illumination since I am not planning on it being used for hunting, though I am happy to hear arguments to the contrary, and good light gathering would be a plus.  My budget is around $2k though cheaper (while still getting the job done) is better.  Used is fine provided there is sufficient CS to ensure I'm not stuck with a dud.

I like the Leupold Mk6 3-18 with the TMR in theory but the LGS doesn't carry that type of stuff so I haven't been able to get behind one myself.  Any word on those or suggestions for a better option?  

As a follow up question any suggestion for a good QD mount that would play well with both ARs and bolts?

Thanks!

The Leupold MK6 3-18 is a really nice scope. Here is my review of it.

A NF 3-15x50 would also be great. I've got one on the way so hopefully I'll be able to do a comparison soon. Only thing is they are a little bigger than the MK6.

Thank you for the link and insight!  Let me know how the NF works for you.