as someone who weighs 140, I have no suggestions other than to say that you will get reliable answers from the clyde section by folks with the same weight as you, not to say the tandem experience here isnt valid, but you'll likely get more answers over there.
good luck with getting the right wheelset for your weight. I agree with the "pay more up front" comments and not have to deal with wheel issues and more expenses, not to mention the hassle.