Looking at upgrading my receiver, want something with a few more watts. Right now I'm limited on space so I kind of have to keep an eye out for how big the unit is. I've narrowed it down to for now......Sony Str 6055 or a Pioneer SA 510 or 610. Advice/experience with these units would be much appreciated. Can get Sony for 150.00 in very good shape and the 610 comes with a tuner and price tag on that was 199.00.