You've got HB's on your Jagmaster, right? Do you know what magnets are in there now? Probably A5's? An A4 would warm the neck, take off a little of the A5's top & bottom ends, and even it out. In bright woods, like maple or ash, it's certainly a good idea. A4's aren't as devoid of treble as an A2, plus they have a firmer low end. If you want something in between an A2 & A4, there's A3's.
I'm using A8's more & like them a lot. I think they're great in the bridge when you want more warmth and a fuller sound than an A5 has, but don't want to give up output like you do with an A2.
With both of these mags, you'll want 500K pots (you always want 500K's in the necK), to keep clarity & definition.
Look up Wymore Guitars.com for magnets. I always get an assortment and meet the $50 minimum for free shipping. That way you can make quicker changes & don't have to place another order & wait.
Let me know if I can help.
Blueman