Funny that you mention this. I just noticed the same thing with the pricing of Black XS, too bad I bought a short while ago, could have got the bigger bottle for the same price I paid for the 1.7oz!
Never personally ordered from them online, but I've bought a few fragrances from them in the last few months and have had positive experiences there every time in different locations. If I remember correctly, they have a warehouse where they ship from, so even if you live close to a Perfumania, you probably won't get it shipped to you super fast, since I'm assuming they don't pull from store stocks like some online retailers do. One thing to keep in mind is that you will probably have to pay sales tax, as Perfumania retail locations are located in most states. Either way, mostly likely that will cost you less than any shipping cost you would get elsewhere.
I'd go for it!