Well with my laundry room set up heat and noise are not really a concern to me, but my electricity rates are so high here that I think the S5 is all I'm willing to pay for for this "hobby".  After I move and see what the rates are like I'll look at the S7 (also after there is a used market for them).  It's fun to me to have a pony in the race, even if it's just 1 vs. the herd.