Quote from: favebook on Today at 01:27:47 AM

Short answer:
If you are looking for reliability, durability and stability, my order would be this (from best to worst):

Canaan>Whatsminer>Innosilicon>Bitmain (with exception of S9 and maybe S19 units).

Long answer:
I've had very few of Canaan and Whatsminer units, but they were always reliable and I never RMA-ed a single one. Everyone I knew who used these had really good "luck" with reliability compared to Bitmain.

Innosilicon is a bit different story, I've had a tad bit more of units that went through my hands or that I used personally. They were all really good and with exception of one T2T's PSU giving me blue smoke after solid 2 years of working (tho it was put through hell - it was used in miner oil a few times, then it was OC-ed to maximum "Performance+" mode during summer)

Bitmain is a complicated one... S9 were really good for me and everyone I knew personally. Out of 100 units that I had and later sold locally, they are ALL still working with OC (using exactly 1.8kW or less - depending on PSU). X11 and X15 were short series not worth mentioning. And then came X17 series, pure hell of units, I've had 75% failure rate on them. S17e was only unit that didn't break even through OC during summer. S17/S17Pro/S17+ all broke even if they were used on factory settings or underclocked. I would never recommend anyone to buy that generation of miners. X19 seems to be better, but more time has to pass so we can determine exact failure rate on them.

it is amazing how i managed to be 17 for 17 on my s17pros. still all work just fine.

s9s were good in general.
if he could score a841 he would like them.

with his 2.5 cent power i would look for gear that can shift psus

s9 ,a841, a921 would all work well with the psu 7empest sells.