Side thoughts.
I have found that some gear is more temperature sensitive then others. As the temp climbs some will draw more power (bitmain) some will slow down a bit (Avalon) some will do both (Whatsminer )
At least that is what I have found with VERY LIMITED use of the older gen stuff. So, depending on power vs cooling it's another data-point to think about.

Bitmain / Whatsminer are more plug and go. Avalon which I do like better and do find more reliable does tend to require a bit more setup knowledge.

-Dave