I have a couple smaller containers for most jobs, and a coleman stacker for the larger ones. A 2-3/8 hole saw in the lid works perfect for the Anova.
https://www.amazon.com/gp/product/B002BMCLMU/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1The issue I see with the more expensive units is that they are typically a self contained size. That's not a bad thing until you want to do something that doesn't fit. Yer not gonna get a packer in anything less than a cooler. My 12 qt will handle a 6-9# butt with no issues.
The biggest issues I see are the wattage, size, and wifi capability. The really expensive units are a 'total package'. You will need to consider the ID of the units bath area. The wifi part escapes me as it does at most times. Why would one put food out when they leave for work, and fire up the cooker 6-8 hrs later via wifi? That's far too long in the danger zone.
My Anova is the regular 800 watt unit. You can get 900W, but what's the advantage? It will heat the bath faster. Just add hot/boiling water to the container first.
It's a selling point as far as I see it, with no real added value. When up to speed; what's the difference?
My medium vessel is wrapped with a welding blanket and retains heat nicely. The slightly smaller vessel will be used for making cheese and sits inside the larger vessel so there are no issues to be had. The cooler is insulated all around and there's little to no heat loss. FTC?
The Anova will heat up any container, so why limit yerself with a more expensive unit?