I have a Shelter 901 and just recently bought the Bent MU SUT. Currently using some other cart, so the 901 has been put aside for a while. Per Shelter's website, they recommend 20 ohms for just about all of their carts. I had some lengthy discussion with John Chapman of Bent Audio regarding the loadings as I was trying to figure out whether there's a way to calculate what the optimum loading would be for a cartridge. He told me that these numbers quoted are just a starting point, you should just try different loadings to figure out what sounds good to you. So start with the recommended loading first, then try different ones to see whichever sounds better. Bent MU came with about 30 different value loadings. It took me a while to finally settled down on one for the cart I am using. Good thing is that this is a deterrant for me to switch cart.
FrankC
FrankC