I've only got about 3K miles on my '05 RL, but have driven a couple of 600+ mile round trips. I found the RL to be extremely comfortable, and I'm a fat-ass, to boot. The Recaros have good lumbar support, good upper body/head support... snug but comfortable.
The last longish trip I took was from Skokie, IL to NW corner of St. Louis, MO... 320 miles. Took 1 hour to go the first 37 miles (Chicago traffic) and 3hrs50mins to go the remaining 283 miles (that last leg was at 73.8 mph actual ground speed, incl gas stop and slow downs due to many, many state troopers within 30 miles radius of Springfield IL.).
IMO, the RL handles like a dream at highway speed. After traveling 250-300 miles at 75-80mph in my old '97 SW2 I would be fatigued and tired... after doing 300+ in my RL at speeds at (and way over) 80mph, I was rested enough to hit the St Louis riverboats for a solid six hours. At speeds of 100 and higher, it handles as solidly as my SW2 did at 50mph. Running my SW2 to its top speed (~105) was a harrowing experience... running the RL at 130 I felt in total control... not that I would ever recommend that anyone speed
