For the longest time I didn't even realize it was there, until my cousin pointed out the "Del Hobbies" sign near the old DOD in penns grove. The hours are pretty good, I think the're open till 9pm most nights.
The guys that run the place are pretty cool, if a little intimidating. They are pretty experienced (old), and know their stuff. They have given me, like a couple of the other reviewers, a break on the price when I bought a few Items. A dollar here, a dollar there, it's not much, but it's pretty cool of them.
Refill prices aren't bad.
They also sell used guns, and they really back up your purchase. My cousin bought a used Automag from them, and when he got it home and found a leak. they took it back, repaired it, and gave it back to him with no repair charges.
Their only weakness is their inconsistancey with what products they keep stocked. They don't have a huge storehouse like a couple of other shops I've been to, so they tend to sell out of items. If you're looking for something paritcular however, they would probably hold it for you when it comes in.
I'm not much of a speedballer, so I can't comment on their field, but I really enjoy visiting their shop. I would definately reccomend looking it up if you're in the south-west jersey area.