Auto-lockers can be a bit "fiddly". Squeeze,twist, pull down, etc. etc. The Magnetron decidedly is not fiddly-squeeze it-it opens. Let go, it closes. If you are concerned about positive action - don't be. Go to your gear store (perhaps Mossejaw...) and feel for yourself. It really is a nice piece of gear.
I would have usually thought twice about paying a premium for gimmicky features. However, I find the opposed magnets to be easier to unlock than a twist-lock or rotating sleeve locking carabiner. The loud double 'click' as the magnets make contact is also reassuring that the carabiner is indeed locked. If you're going for an autolocking carabiner, go for this one.
I really like the magnetron line since they are the easiest to operate of all the autolockers I have ever used. Specifically I use these to clip into the anchors on sport routes. They can be easily be opened in a second with one hand and I enjoy the peace of mind that my carabiners are locked when I take my hand off them. Overall this is a bit pricey but totally worth it.
The magnetrons are really helpful when you need to operate a biner quickly with one hand. I like using them for clipping into anchors when I'm pumped out and struggling to make that last clip. It's also really nice having the peace of mind that my biners are always locked when I take my hand off them.