Bitmain is good but many miners are out of stock very soon, so I have bought miners from other suppliers. Based on my experience, Hashcube is quite good and Eshore(not remeber very clearly), especially the aftersales services!! They gave me lots of help when I first invested in mining machines. BTW, do you know any reliable mining hosting companies? Now I have my S17 hosted in their Hashmax platform. The electricity fee is pretty low and alsomt 100%uptime were guaranteed during last two months.. but I'm still waiting to see its general performance and at the same time look for cheaper electricity.