Im not sure if this is the right place to post,but im quite sure.
Im going to be getting a jackson ds30dk.i was wondering if u think it is ok to get an Emg 81 for the bridge position?

Also i belive they are a active pickup?
How long would the batterys usually last?
Thanks guys.
my gear:
jackson dk2m
ibanez grg170dx.
peavey vyper 15
warwick corvette 5 string
ashdown 5 15
Yes, an 81 is an active pickup.

You don't need to worry about the battery, it will last for a long, long time.

I've heard that the 81 makes an excellent bridge pickup.
Yes, the 81 is active.
The batteries last damn long, as long as you leave your intrument unplugged when it's not in use.
Do not forget to unplug when your not playing, so it doesn't drain the battery.
I have two guitars with EMG's, a Gibson SG standard and Esp Eclipse and they both have the 81 in the bridge and I really like the sound. The 81 is a good bridge pickup man, I really like it.

It just really depends on the type of music you play though.
If you play a lot of high gain music then it might fit you a little better.
I'm not saying the cleans aren't good, because they are- but if you're looking for a good bluesy or clean sound you would probably like a passive pickup setup. Look through the forums man.

think about getting a better guitar/amp before considering swapping out pickups.

the jackson js30 series is really quite poor - save up for a japanese made one.
Be careful though, I believe the 81 may be kinda trebly for a alder bodied guitar I think some people use the 85 in the bridge to balance out the sound. But if you are going for a treble sound I'm sure it would work to have the 81 in the bridge. Btw What kind of amp you have?