any experience with Firearms Support and Storage in Whippany?

Experience with what part? Storing guns or buying, transfers, etc?

interested in buying-do they have inventory?

Would never set foot in there again. Bought a gun there that was defective. Owner told me if manufacturer repairs it, it's mine, if they replace it with new I would get a full refund towards purchasing something else I wanted to buy a higher end gun through them, I wasn't trying to take my money somewhere else. Manufacturer replaced it with new and then they tried to pull some bs. Got my cc company involved and they decided FSS  were screwing me around and found in my favor. I'm sure plenty of people have bought there without issue, but their true colors were shown when a problem arose. I ultimately ended up buying through Tom Kattner at Oakridge Firearms and would recommend him.

I buy there all the time. They have a lot of used and milsurp inventory. I've never had an issue with anything I've purchased from them, new or used. Sorry to hear about tjs3023's experience. They've always done right by me.

And I also buy from Tom at Oakridge, great guy as well. I was just there last week putting money down on a new milsurp piece.