Granted, I am not taking into consideration that heat sink, so my post may be null and void. I guess I need to look at the costs of the U2 to see if it is cheap enough to make up for the amount of space it consumes.
Here is what I use for U1's:
http://www.amazon.com/gp/product/B004BV7XQ8/ref=oh_details_o04_s00_i01?ie=UTF8&psc=1I have one with 4 running on it, but I see no reason you could not do five, though I did not find them capable of handling 5 block erupters, each. I use one port for a fan, one port to chain a second USB Hub, and one port for 1 BFL 8GH miner.
They are cheap, seem reliable, as I ran BlockErupters on them before the U1's, and work with a Rasberry Pi. I do overclock my U1's and these USB Hubs do handle it.
I also have this:
http://www.amazon.com/gp/product/B005NGQWL2/ref=oh_details_o06_s00_i01?ie=UTF8&psc=1It can easily handle more miners, but it does not work well with Linux, did not work at all with the Pi and makes my Windows PC not boot when it is plugged in. Plus it is expensive.
I hope that helps, but I know there is also another thread, on Bitcointalk, on USB Hubs that have been tested and to what extremes.
