SDXC and UHS-1 readers

I have a Sandisk 45MB/s Extreme 32gb SDHC card for my T2i. I was hesitant to buy a 64gb sdxc because of the limitations regarding card readers.  I understand that, although I am currently only getting a maximum of 4-20mb/s transfer speed to my pc wih usb 2.0, I can get faster transfer rates with a usb 3.0 card adapter for my PC and a usb 3 card reader.  I also understand that for use with SDXC cards I will need a special SDXC card reader.  Then there’s the UHS-1 thing.  Do I need a card reader marked UHS-1 to get the maximum transfer speed.  Has anyone tried these usb 3 adapter cards and usb 3/SDXC/UHS-1 card readers?  What is the real world improvement in transfer speed to the PC with the use of these gadgets?