I have one, in fact I have the exact one you're asking about. 63QT ARB, the newest one. My plan is to mount in in the bed of my Tacoma when my GoFastCamper gets here (the end of this MONTH!!!). I have a Decked Drawer system in there and already have a tilting Alu-Cab slide to lower it down to tailgate level (wife needs access too).
All that said Right now it's mounted to a platform in my rear seat and Hardwired using the ARB Wiring kit directly to the Battery. To be completely honest I don't have experience with other high end Overlanding Fridges, but I can tell you there is NOTHING about this fridge that I don't love. It's absolutely enormous and fits enough for a week plus +++ for my wife and I.
Battery consumption is very low, my Tacoma only has the stock battery and it hasn't drawn it down yet (running max 28 or so hours without the truck running) It of course has three levels of low voltage shutoff to protect your battery so it should not be a concern. I do plan on switching to a group 31M Deep Cycle/ Combo Battery shortly simply because it's not good to draw a starting battery down.
I have the ARB Fridge cover and remote monitor as well (since it's ultimately going to live in my truck bed) The monitor is super cool, shows current battery voltage and fridge temp. I got the fridge in spring and used it for a 5 day trip to Vermont, and than for an 8 day trip through VT, NH, and ME and it was perfect.
One thing that I do is when I put it in my car and load it up the night before, either I keep it inside and plugged into 120V to let it come down to temperature (that's what uses most of the power) and or lately I've just been running an extension cord to my truck the night before since it's got a smart charger that picks up 120V and uses that first if available.
Headed to PA next week for an Overland Rally for 4 days so I'll be testing it some more but all and all it's perfect. The one thing I will say is it may be nice to have one of the fridge/ freezers with two compartments just be bring frozen foods along. Though for the cost and size if I want to do that I may just add a 37qt and use it strictly as a freezer if I really ever think I need it. Once you have ANY real fridge you'll wonder why it's not the first thing you bought. Oh and keep in mind a 63QT fridge is at least the equivalent of a 120QT Cooler since you have NO ice to waste space. You'll love it.