I've had a red-top optima in my New Holland TC45D tractor since 2006. I paid $112 for it on sale at Sam's Club and it has been both reliable and trouble free. Previously, I had battery acid leaks that destroyed one radiator and two HST cooler hoses with metal tubes. I also had to rebuild my battery stand because the lead-acid battery leakage destroyed it. Since the Optima, not one starting problem nor any problems with leakage or dirty terminals. I leave my tractor sometimes over a month without starting and it fires right off. In winter, I leave the tractor outside and the Optima has supplied full glowplug power and a prompt start in 8-20 degree weather.
Gary, I don't know if Kubota's price is $200 on your battery or if that is the going price everywhere. You didn't say if it was a yellow, blue, or red top battery. The redtop is a starting battery and not designed to deep cycle. If you bought a regular battery and are happy with it, that's awesome. However, many of us are thrilled with the performance of our Optimas and would go right back and buy another if the current one failed.
In my diesel pickup, I use Autozone's Duralast Gold batteries that are full replacement out to 3 years and then prorated out to 8 years. Those have also been excellent batteries in a standard lead-acid configuration. I don't see any reason to change to an Optima in my pickup.