Thanks miner29, I've just ordered them. I'll let you know if they work. Unfortunatelly, I don't know if I can or how to give you merit. 
When i have chained them off each other ive stepped up to a better multiplexer chip. SQRL X2G is very good chip but way more exspensive. But if you are going to run just one in a slot not chaining one off the other then the cheaper option is fine.
I suggest starting with one and adding a gpu at a time and get it running. This way you can figure out what the limit is.
No worries on the merit man. Just hope it helps ya. One miner to another. 👍