If possible, you might want to rent a Kubota with a mulcher. Get it out there for a few days when it is really hot and dusty. Try running it all day, or even a half day, before you make up your mind. I have quite a bit of experience with these, and I think you need to try before you buy. That includes the Cat, as well as the Kubota. Another issue is how fast the head can recover after you stall it, or almost stall it. There are a lot of goods and bads to both makes. Just be sure you know what you are getting into before you spend all that money. Good luck.
Jeff
I'm mulching with the open ROPS SVL95 now, it turns my 5' head well in the brush and recovers quickly if I big it down. I can't really run it into a live oak tree but, that's a really hard wood and I wouldn't expect anything other than a 200HP+ purpose built machine to handle that.
To some extent, if the AC coils at all, it's a bonus over running the mulch head in an open cab with a fan and the truth is, I'm not going to run it when it's 100° outside even if the AC has it 60° in the cab because the mulcher heat soaks the hydraulic system as it is. 4 hours in the morning or late evening is as long as I want to be running it anyway, my terrain is very hilly and rocky so the rude us as tough on me as anything else.
I always stop every 3-4 hours to grease the head and clean everything out with my big 185CFM engine driven air compressor when I'm mulching. The machine gets filthy, in the cab especially. Right now, I keep the head low, almost never more than 2' off the ground, to minimize what comes at me, even though I've made an expanded metal "safety" door, it sucks when little bits come through and pepper me. Keeping it low has kept most of the debris off the back end, most of what ends up there is actually limbs and stuff the machine broke off, not mulcher debris.
I'm not buying new, current machine is a 2017, I'll probably be in the same vintage. If I get a Cat, I'll have to go older to stay in my price range, I'd really like to not go over $50k. I paid $34k for the SVL95 I have at auction last year, it had about 2200 hours on it when I bought it. I can get a 2019 cabbed SVL95 for less than $50k, the Cats are almost all over that.