I have a Lufthansa FCL lounge voucher that I need to burn.

I have travel taking me through FRA on the outbound (it's an EU flight, so I'm not otherwise entitled to access any F/HON lounge), and MUC on the inbound. Assume I have equal, but decent (around 2hrs) time to connect in both directions. I have, to this date, experienced: the FCT (which I know this voucher doesn't entitle me access to). FCL B (FRA), the old MUC FCL, and the brand new MUC FCL. I have yet to experience FCL A in FRA.

I'm connecting to MRS on the outbound, so assume I'd leave from A pier at FRA. Am connecting to LHR on the way back, so not sure where I'd leave from at MUC (I don't go through MUC all that often).

Which lounge would you recommend burning this voucher on?