I’m probably 50/50 on buying stuff local compared to online. I like to support local shops as I like to try stuff on but there is just no way they can have the same stock or prices as the large warehouse places. If a local shop has what I want at a reasonable price then I will buy from them. Too much of a mark up and I will look elsewhere. It’s hard for my local shops (Seattle) to be competitive as the local sales tax is near 10%. Motorcycle Superstore is just down the road in Portland with zero tax and free delivery on most orders. Being so close that’s 2nd day delivery. Still, I buy local when I can.
As to what online stores to buy from, I’ve not really heard of any bad ones. Other than the ones mentioned above, I’ve also bought from sportbiketrackgear.com and revzilla.com.