I thought I'd follow up my own post and share what I've learned so far.
According to pdf documents at Times Microwave's web site (
http://www.timesmicrowave.com/wireless/index.shtml), the outer diameter of both the LMR-195 and the LMR-200 is .195". Not sure if that's a typo or not but even if it is and the LMR-200 is actually .200", a .005" difference seems insignificant. Sorry, I don't have a caliper to measure the diameter with.
The major difference, other than how well they carry a signal (-4.8dB per 100' for LMR-200 vs. -5.6dB per 100' for LMR-195 @ 220MHz), seems to be in the size of the components that make up the inside of the cable. This is something that is insignificant for solder and crimp type PL-259 connectors, however the larger center conductor (LMR-200 is .044", LMR-195 is .037") makes it difficult to attach the center pins for RG-58 type SMA connectors. Specifically, this means the gold plated crimp/solder type sold at RS (With a teflon dielectric, amazingly enough! Imagine my surprise when I saw they actually had the connector in stock!) I had to use a small file to reduce the diameter of the center conductor before I could get it to fit in the center pin for the SMA connector, not my preferred way of doing things but sometimes you just have to make do with what's available.
I also found the center conductor a tad large for the center pin on my Larsen NMO mounts, but a needle-nose pliers helped me push it right in.
My reason for choosing to use SMA connectors was this: First, my Yaesu HT has a SMA connector, so I can just plug it into the radio without adapters. Since I also have this hooked up to my PSR-500, I liked the signal characteristics of the SMA connector at higher frequencies vs. PL-259 for monitoring my local 800MHz P25 system (I doubt the minuscule signal loss from the SMA to BNC adapter has caused me any great harm.) If I ever use the HT enough to wish I had more power, a SMA to PL-259 adapter shouldn't cause me any real harm should I choose to hook it up to a mobile with some real output power.