I am 5' 10" 170lbs and the vertical seams on these two seats really bothers my spine. Others have commented that their belt loop gets stuck there too. I have 20K on std seats and have just installed 5 Star Blue Ribbon sheep skins to "fix" the problem. The only complaint now is that the lower back isn't heated as well. Previously the lower back area would be hot in a matter of a min or so (Girlfriend not happy about this, but she does like the feel of the new skins, thanks to all who rec. them, they are truly top notch). I will order the Comfort seats in next e39. BMW please change the lower back leather insert to one solid section!!!!! Good Luck REV 99 540 iT