I agree with Jon on this one...you really should ride both bikes, b4 making a decision.
Past that...the Magna is (as you say) a '96 model.
So that means the Magna will have an o-ring chain drive.
The Vulcan, on the other hand, will have a shaft drive.
Read up on the responsibilities of caring for a bike with a chain drive, b4 you buy one (if you're not aware, already).
It will involve a lot more attention, and effort...than the shaft drive. It's also considerably messier--cleaning, and (re)lubing a chain. This will need to be done on (at least) a periodic basis, assuming you want to truly take care of the bike.
A chain and its sprocket will have to be replaced every 20-30k miles, or so (vs the shaft, if cared for, will last the life of the bike).
This model Magna will not have a centerstand. Thus, loading or servicing (or fixing a flat) on the Magna will be more difficult.
The Magna will use more gas....but will be noticeably faster, as it was one of the "power cruisers".
Love the look of the Magna's pipes--2 on each side, very cool!!!...
Also, if you are a new(er) rider, stay away from the Magna, until you have more riding experience. In that case, the Vulcan is a much better bike for you, anyway.
Past that, both bikes were built for quite a while, so spare parts for either should be no problem.
You might also check out any Magna internet forum(s), to see if that bike had any chronic technical issues.
Hope this helps....