I support my LDS, not only for the availability of air/nitrox fills, but also for the availability of good used equipment at great prices. They may be more expensive for certain things, such as reg service, but when it comes to other things they have been very competitive in pricing compared to Scubatoys or Leisurepro. They also give me the option to pay them over time for my new gear. I just got a new Sherwood Axis bc for around $75 cheaper than I could find online, and they took my old bc in and gave me $100 for it. I just got two used lp112's that were just hydroed and VIPed and O2 cleaned for $400. (a new one goes for about $350, and I got two for just over that) Then there is the availability of the pool for trying out new gear anytime they are open. They schedule trips all the time and I have yet to be able to beat their pricing when I have tried to go around them. Don't get me wrong I have bought some items online, and will continue to do it, but I buy the little things online; clips, lanyards, mask straps, fin straps, etc. I will be needing a pony bottle this season, and yes I will buy that and a new reg setup from my LDS. They will not only give me advice not based on making a sale, but advice to get me into what I will need for then and the future.
Just my .02