Derek,
Your LDS is a business. He earns his living by selling things. If you want to buy something that he doesn't sell, he doesn't make a penny. I'm not saying that your LDS is giving you bad advice just to make a sale, I'm just pointing out that if you go into a shop that doesn't sell X and ask about X, he's probably going to tell you why you really don't want X, you want Y, and he just happens to have a nice supply of Y right over here and at a very nice price, too.
It is important to have an ongoing relationship with your LDS, and it's important to support them. You want to have that local guy 15 minutes away that you can go to with problems, get air fills and continue your education. Within reason, I'll always buy the thing I want from my LDS. I can probably save 15 or 20 bucks by buying it off the internet, but the internet stores aren't going to help me when I have a problem. Not to mention, I'd feel like a jerk walking into my LDS with something I bought elsewhere and asking them for help. But if they don't have what I want I'm not going to buy something else just because it's what they have on hand.
The best advice I can give you is to establish a relationship with your LDS, so that they don't just see you as a potential sale. Go diving a few times with them. Go diving a few times with other shops. See what you feel most comfortable with. (Shop A rents brand XYZ, shop B rents brand ABC.) See which shop you feel most comfortable with. The guy at the shop 45 minutes away may turn into a good friend, the guy down the street might be a jerk. You'll never know unless you meet them both.
As far as which BCD to buy, as was already pointed out, you can do rec dives with a BP/W, you can't strap a pair of doubles onto a vest. Try them both and see which you like.
Paul