I have the 2810HST and it runs a 5' Woods BB60 just fine. I would think the 3510HST would run a 6' cutter. It has 28 hp at the pto vs. mine with 22.5. I believe they are both the same basic size with different engines. I just cut part of my field with 3' tall grass and it doesn't bog down at all. The grass was a bit wet but, but i cut when I can. The rain started again and drove me back in. It didn't last long and I'm headed back out.