The FPS you set in the UT Menu is only the minimum FPS you want - then if needed to keep you there, UT will lessen or omit graphics in an Attempt to keep you at that minimum FPS.
That is all that does.

It's not a problem if not affect your moving speed of the player.

The wisest course is set as screen monitor.

Lock it to the refresh rate of your monitor (usually 60hertz hence 60FPS). Any higher and you get tearing when you turn quickly.

In the old days with large CRT monitors you could crank that to 100 if the monitor could handle it but now all the monitors are LCD and can't do anything but 60. I miss the response time of the CRT's but the colors are better with the new monitors.

I have always wondered if players with 120 plus fps on 120 hz monitors can see players with 60 fps on 60 hz monitors before they see them.  My monitor is only 60 hz, so the times I have removed Vertical Sync and my fps went to 150 plus, everything (bots, weapons) moved really fast. Too fast. Bots were in my face faster than I could shoot.  It's much smoother when all my settings are 60 fps and my netspeed is around 7500. I wish I could see the game from a 120 hz monitor with 120 fps.  I really want to see how the game looks at that speed.  Mortgage and kids means old monitor for now....lol.

My math sucks but even if you had an old PC and stuff at 60mhz for the refresh and someone else had 120mhz refresh they still only see more or you faster about 1/60th of 1 second faster or something that even at half as fast or twice as fast isn't noticeable to the human eye I'd suspect.

I finally went to a pair of flat screen LCD monitors from a bad to the bone Sony I still have. I can tell the Sony was better but these new monitors I'm using which are old Acer AL1916 monitors get it done more than well enough. No heat hardly and much less power consumption and desk space required. It was a no-brainer once I did it.

I still use a CRT because I like it. I tried playing UT on DELL flat-screen at 60MHz refresh, didn't like it. The game looks different on a flat-screen, and feels different. As for FPS, I can't see any difference between 60fps and 100fps on my system. My CRT is a LaCie electron 19 blue III flat-screen. It has beautiful color and a decent refresh rate of 75MHz at the highest screen res I can set in UT.

For me, I'm more concerned about color, brightness and contrast for working in Photoshop. I re-calibrate about every two months. So if you see me saying "map too dark" it is because IMO how it should look. I know my brother, JamesBong, likes his monitor bright, but when it comes to graphics, it sucks because you have no idea what it will look like printed out on good quality photo paper on a good quality printer.