When I replace the standard wet cells that come as original equipment in most machines, I do the same as OOSIK does and buy a top of the line expensive battery to fit the space. For me, this is usually this is an Optima AGM type in their distinctive red, yellow, or blue case colors with the round cell shape.
I've never tried the Odyssey, but see is no reason to doubt their claims - some of their claims about lead purity are similar to the Optima. I think it is possible to manufacture a premium battery, and expect that they just cost more to make.
After all, If the battery doesn't work, the tractor isn't going anywhere. That in a nutshell is the main reason I buy premium batteries.
The second reason is that since in my experience they tend to last enough longer than other batteries it makes the long term price the same as a cheaper battery. And if that's so, then why not enjoy the advantages?
We're dealing with averages here. I buy what I do because all the above is generally true... not always true; just most of the time.
I've had Optima batteries that were duds or didn't last, and I've had cheap wet cell batteries that outlasted all expectations. I've got one of those wet cells in the Kubota right now. Twelve years and going strong. Although I'll say that during its astonishingly long life its wet cell fumes have corroded the paint and metal of battery box area and ruined two sets of battey cables. So has it really been worth the price?
rScotty