I buy from both, but prefer to buy locally. I'd suggest you consider establishing a relationship with a local dealer. In the long run, a few dollars more will be offset by having someone who gives you personal service.
I would like to buy locally but won't put up with the attitude from my local photography store. It is such a snooty unfriendly place to shop. The owners seem to have their small number of "favourite" customers that they will chat with endlessly while ignoring other customers.
One Saturday (a pretty busy business day), I saw a line of customers with photographic equipment in one hand and a credit card in the other hand, just waiting to give my local store money.... they were ignored to the point that far too many of them simply left. Why? Because the owners simply had to tell a long and boring story (yeah everyone in the line had to listen) instead of helping customers spend their money.
I am not a big spender on photographic stuff, but I buy a lot of small stuff on a pretty regular basis. I always felt that I was disturbing the owners with my tiny purchase. But guess what? Like most photography nuts, there came a time for an upgrade.
About 3 months ago, I purchased just under $6,000 worth of camera/lenses. But not from my local store. I went with Adorama/B&H. Got a better price, better customer service, and no attitude.
Note to local photography stores: Lay off the attitude. A small purchase customer today may be your big purchase customer next month.
Gone are the days where we had to deal with our local stores. The question is no longer "why shouldn't I shop local" but "why should I shop local". The attitude of the local shop owners governs the answer.
I would much prefer shopping local. But I don't deserve to put up with their attitudes.