I have not owned a Mag since the Level 7 days, but I have owned a lot of Vectors. I would say the Mag is going to be more reliable for you. "Old school"? Maybe not so much, but if you want to stay more competitive and shoot every game, go with the Mag.
That said, a Vector is plenty fast for most speedball and so loud that you will basically negate the other teams ability to communicate with one another, especially if you shoot a lot and it is a smallish (or
indoor) fields.
Also, the Air Power Vector is STILL the most accurate (read as; the whole package consistent + comfort + pointability, etc) paintball gun I have ever shot. And remember, I have never shot an E or Xmag.
Good luck,
D