I've ridden a couple BMW bikes. My husband owned a 2000 BMW K1200RS (now deceased thanks to a careless taxi driver), the last generation of the "Flying Brick" motor. Despite proper maintenance, oil seeping into the dry clutch assembly because of deteriorating seals were a huge issue and the clutch plates were on their way to a second replacement at only 88,000 miles. For this bike, replacing the clutch would require having the engine and shaft drive assembly dropped and taken apart, a job that requires a quoted 12 hours of labor (big dealers charge $90/half hour). The FJR is a wet clutch like every other long-lasting Japanese bike and with my daily commuting habits I'm still on my original clutch at 100,000 miles with no slippage whatsoever.
I also had the chance to ride 500 miles in CA on my friend's 2009 BMW K1300S. I enjoyed its raw power, smoothness, and performance (it's an FJR with a more sporty posture, a 150 lb. drop in weight, and 20 more ponies) but after hearing about the recalls on the ECU, maintenance costs, and things he needed to do to perform maintenance by himself (a $350 engine computer code reader, $100 for a digital version of the service manual, and the usage of semi-synthetic Castrol oil as not to void warranty according to the dealer) having a bike like that was completely impractical both financially and as an every day machine.
IMO, the FJR is a cross between that K12 and K13 with the capacity to tour and the speed and grunt to keep up with just about any bike out there. Its greatest value to me is how little maintenance my bike has needed and how much I've saved because of its simplicity. Valve adjustments/inspections @ 26.6k mile intervals, standard fluid changes, the occasional once-over and it's ready for the road. Also, in an extreme case, if you've read the stories of Iron Butt rallies and BMWs, many riders on the RT bikes have to carry replacement shaft drive assemblies because they've been known to fail toward the end of the competition. If you're a mile chewer that wants a bike that will just keep going, I'd go with the FJR.
And lastly, one of my favorite perks to having it for the cross-country trips (and I think it's because I'm a CA expatriate): FJRs LOVE REGULAR FUEL! 87 octane FTW!
Good luck on your decision making. I enjoy riding the Bimmers for kicks but I can certainly attest to the FJR's ability to just avoid service departments all together.