I'm a new diver and new to ScubaBoard. Coming from the IT world, I can understand the firm loyalty that people feel towards things. And from what I've seen on ScubaBoard, it's not just LDS vs. Online, it's almost anything. DIR, DIY, this reg vs. that reg, and substitute any brand name or product in there (computer, BCD type, etc, etc.) And having been around the Internet for a while, no matter how someone preaches, the person with the opposing view will NEVER change their mind. What does it usually bring? 14 pages of back and forth debate with the occasional lapse into name calling and raspberries!
Scuba products are really life-saving devices. If yours doesn't work properly, you could be seriously injured or killed. It really doesn't matter where you buy or have your gear serviced. You have to TRUST that party, or yourself for the DIY crowd. If you don't like any of the LDS available in your area, or can't find one reasonably close, don't use them. I wouldn't in that case as I wouldn't put my life in their hands. If you do find a good one, then excellent. Use them.
I personally have a very good relationship with my LDS and in the 2.5 months I've been diving, have gotten to know them fairly well. I bought my basic kit there, fins, mask, snorkel, boots and weight belt, and took my OW through them, getting a referral to take my OW dives in the T&C. I liked it so much, I looked around and ended up buying a package from an online retailer for BCD, reg, octo and computer, all for a price lower than my LDS cost. I just got back from trying it out in my LDS pool. They understand economics, and that if I can save that much, then my budget is stretched to do other things. They have created a good value-added service, pool nights, trips, dive club, etc, that keeps me there. I have bought a bunch of other stuff there also, slate, light, knife, etc, and I will keep going back as it is convenient and I trust them. They are also an authorized dealer for my reg, which is why I bought that particular model.
/rant off