How many of you guys have or do not have a TPMS?

Have one. It's the only way to know what your air pressures are while rolling down the road.
I't also, a very simple way to check tire pressures before heading out.
Pat

Speaking pedantically, I think probably everyone here either has or does not have TPMS. :B

I do not for my motorhome, but my car (as with all new cars) did come with one. I make it a general rule to check the tire pressure in the motorhome daily when driving, and give them a quick once-over visually and by feel (checking for obviously too hot tires) at gas or lunch or whatever stops. While that's the general plan, I will admit I occasionally cheat a bit and skip a daily pressure check.

I have one. It has saved me from major hassle finding a leak while I could still drive to a shop. It also relieves you of routine manual checking of tire pressures. It really contributes to my piece of mind.

I've had one for 10 years. Had to learn the hard way before I bought one.
Just last week I discovered a slow leak in one of my car tires. Works good.