Yes, you'll need the PSU.
True, my setup is going to be 3BTC 4LTC 2ETH which will leave some tokens to rent while I wait for them to make more coins available (Z-cash?) and I get a better understanding of the business.
I would contact head of sales, Hayden Gill at giga-watt directly: firstname.lastname@example.org. He's generally very responsive, whereas the ordering process on their website doesn't always get a response.
I think so too. The team at giga-watt has access to the cheapest electricity in the world and really seem to have thought long and hard about optimising the mining pods. I'm very excited. Good luck!