People need to remember that most all the "Fuel" blenders for models these days are cottage industry operations not giant chemical plants. (With the exception of VP Powermaster) and even that is a very small subsidiary of VP Racing Fuels.
The Federal and local regulations on these businesses is unbelievable and has driven many of them out of business over the years (including Sig from the looks of it) In Particular Nitromethane is very difficult to buy and the requirements to possess and store it in larger quantities require "Fort Knox" Government approved security and miles of paperwork.
Shipping is an almost prohibitive cost in any small quantity and with the demise of most local Hobby Shops large shipment of pallets to warehouses for Hobby shops is nearly dead. If you're trying to order a couple gallons or one case, these venders have no control of the cost to ship to you.
Of the venders listed Randy Ritch of Ritch's Brew does the most for the Hobby. He supplies (donates) all of the fuel for CL Combat, CL racing, and Pylon Racing every year at the Nationals as well as selling fuel to customers who want to stock up. He also supplies fuel at Several large combat and pylon contests during the year.
I make all of my own fuel because I fly things that require different types of fuel and making it gives me more flexibility. I have purchased ingredients from FHS (Red Max, S&W fuels, and Randy at Ritch's Brew over the years and didn't have any problems but I didn't expect super quick turn around. Years ago I bought ingredients from Don Nix of Powermaster when he was in California and later in TX. After he sold the business to VP Fuels they wouldn't, and still won't, sell ingredients to me, although you can buy their Methanol and 50/50 from local speed shops. Morgan (Cool Power) has never been controline friendly in my experience and refused to sell me oil so my opinion of them is negative.