GPU Mining alt coins or 3x Antminer S9

[casperround]

Hi all, right I have 10k GBP To play with, I've been looking at antminer S9's however the price has shot up allot. so I can only get 2-3 S9 miners,
If I where to spend it on making a mining rig, what would be the best power I can achieve for 10 grand? What speeds can I expect and what cards should I go for