If you are familiar with the downsides - as it seems you are - then go for it.
I have some mining since 2014 or so and still going strong.
They are beasts as you say, but noisy and hot!
I have a few those cards. I undervolt them so that they are not so hot and noisy.
I always set the fans to 100% for R9 290/290X except for 390/390X (using manual temperature graphic setting). Even I add additional pwm fan's in the front of cards. This rig produces a sounds same as ASIC miner, lol.
Undervolting pretty good to decrease 2
o-4
o C.