Have had good experience with Divers Direct, not that store, that may be where the problem lies!
As for VAT, it gives you the full price you will pay out the door rather than having to roughly guess what sales tax you will get added to your bill before leaving. I prefer to know in advance, even though it is 17.5% rather than only 6-8%. Phaethon, when checking out the DD prices, remember to add on somewhere around 7% (dont know the Ft Lauderdale sales tax amount, but 7% is average in central FL) to the total of the items you are looking for. I also dont know if you have to pay tax on them when you take them back into the UK, cant recall on that as i havent taken large expensive items back to my family over there (yet).
PS. If you have good LDS's that value your custom and work with you, you can pretty much beat the LeisurePro and other online store prices on most packages of gear, not individual items though.