I’ve owned both Mag 10’s and Scotty HPs (among others).
Both are great riggers and you can’t go wrong with either. Definitely the top two non-computerized riggers in my opinion.
The Scotty HPs are insanely powerful and fast, and I like their tip-up boom. The also have a softer stop to them, but I still use snubbers (I mainly run 15lb balls). My only gripe with the Scotty’s is when winter fishing the stop beads can get jammed in the boom roller if it’s building up with ice (doesn’t happen often, but if I’m sending them up and down a bunch in the teens it can)
The Cannons have a more reliable auto-stop, but they stop harder. I’d definitely recommend using snubbers with them. They don’t tip-up either, but it’s not a deal breaker.
Unless you plan on fishing deep often (100′-250′ down) and with big balls, the less expensive Mag 10’s will easily suit your needs.
They can fish deep too, but the performance of the Scotty HPs blows them away, both raising and lowering.