Note that with your actual gear inside the pack (rather than weights). it's going to be a whole new ball game. This is why it's generally advised to wait to buy your pack until you have most or all of your other gear. If you can box up your other gear, plus the weight/bulk equivalent of a week's food and water, and take it to the store (preferably by appointment at a non-busy time), you will probably have better results.

Pack fit is almost as individual as shoe fit. For example, I have not yet found an Osprey hip belt that wasn't extremely painful to my hip bones. I've never tried a Deuter pack (too heavy for me) so don't know how that one would work for me.