Having used both I would go with the Talleys and they make them for that FN...I have had a couple of reports of the Leupolds breaking at the small part of the lever..however I am sure that Leupold would stand behind them,as they do all their products..

The original Leupold QD mount setup is one of the most underrated pieces of kit ever. Mine on a stainless Win classic .375 have been 'bulletproof' under the toughest conditions in Africa, and the low rings are some of the few factory jobs that are low enough. I have Talleys too on other rifles but the Leupolds are simpler and heaps easier to lap. In addition,the smaller levers I find less 'snaggier'than Talleys or Warnes.
Good luck!

I have Leupold QRW rings and bases on most rifles I own, including my 458 Win Mag, 375 H&H, 338 Win Mag, 300 Win Mag, 300 H&H, etc. etc.

They hold up great, return to zero, and are very convenient.

Tim