Mostly for me it's the ability to get things in a couple of days, and not having to pay for shipping. And getting liquids shipped is nearly impossible. And now with the dollar falling, I find the cost differences to be not so great. It's not like I order so much C41 that it makes it worth it to deal with powders and pay for shipping and HST, and quite often, brokerage fees. I get my RA4 from the local lab.
That being said, I AM in the market for a couple of C41 packets to try, and some crystal archive... but, beau photo's pricelist is offline.