There shouldn't be a problem using the Speed Hunters with a Whisker or Whisper Biscuit. If you like them offset, I wouldn't go more than 2 degrees and that may be pushing it. I like the Speed Hunters better than the 4 inch Quick Spins, because they fly exceptionally better. If you can, try shooting with a normal rest. You'll be surprised how easy it is. It'll take a few trys to get your form down so your arrow doesn't pop off the rest. At the moment, I'm using a fall away, with bitsy forks. If my form is really sucking I immediately know it, because my arrow takes a dive off the rest.
As far as mileage...oh...you can play that card for a few more years. lol