i can land 5s consistently, but when i go for a 7 i either get to 540 630 and land all sketch and crash, or i just mess up and go all corked right off the lip and dont get past a 3.
when you're setting your spin, do it from your hips instead of your arms or shoulders. you'll get more rotation that way and the bigger the jump the easier it is to get it around and stomp.