The Pi won't be the issue here; in fact, it's much better than using a Windows host.
However you must ensure that a) you get enough power out of the ports and b) the power is dissipated.
The former can be solved by a good hub and PSU (which you have) and the latter by good cooling.
However, you can also aid both of those at the same time by lowering the power consumption by veeeeeeeeery slightly reducing the core voltage using the screw in the bottom right corner. Since the sticks are tuned to run at 400MHz, they may not be exactly 100% perfectly set up for the absolute maximum overclock and there might be some performance to be squeezed out using this technique.
thanks for this, which direction would i be turning? and which side of the miner would be the top?
Turn it clockwise. But really barely turn it; if you see the screw turn it's almost too much already. If that wasn't enough, you can repeat it 2 or 3 times, but I think you don't want to turn it more than like 1/8th turn from how it ships, at maximum.
The heatsink is on top if you plug them into e.g. the GekkoScience hub.
thank you so much! I finally got it hitting 500 Mhz - quick question what would happen if i moved the screw more than 1/8th from its stock position? I'm just wondering if I would be able to hit the 800 frequency since the hub has 6a per 2 ports