I have a mag 20 and a mag 10 on my boat, have fished with both brands, my buddy has the scotty propacks, and I will say this, both fast, but the electronic stop on the cannons can cost you gear. If it doesn't stop in time (weeds or seagrass on the wire), the cannonball slaps the end of the arm, breaks the wire, and all goes in the drink! If you add up the snubber, terminator, ball and release, got near $40 hanging on the end there. I have talked with guys that have had more trouble with scottys though, mostly with the clutch, some with electrics, cost them gear too. All in all the mag 10 has been the most trouble free, just a longer wait from the bottom, and the chance for a nice fish to get around the wire and break off... Mag 20 is a lot of money, mag 15 is as fast and cheaper, scotty is probably a better deal, in fact you could almost get 3 pro-packs for the cost of 2 mag 20's if you shop around...