I can help you part way. I just bought Select Shades from Tradewinds, got it this previous week, and everything was in order. Tradewinds sent appropriate emails acknowledging my order and telling me when my order was shipped. The tracking wasn't in the email but was available from my account at the site. The package was delivered on the expected day by UPS, and the contents were packed appropriately. The only thing Tradewinds could have done better would be to put the tracking in the email for my convenience, but the rest of the service was absolutely perfect. I too had read the negative posts about Tradewinds but my experience contradicts the bad reports.
I've only used Select Shades twice but they appear to be okay. The liquids are nice because they are easy to mix with soap batter without the problem specks you can get with powders. The color gamut is limited, and for example you won't be able to make blue. Or brown. Visit SelectShades.com and look at the selection charts and if you like the colors then you might like the colorants. Be warned that a lot of their colors are just light, bit darker, more darker and darkest. They give the impression of being more colors than there really are. All in all I think Select Shades will be useful to me but will not be a "solves every problem" solution.
You should add another choice to your list: TKB Trading and their powdered pigments. Look at the pop and lake colors. If you're interested then order a sample kit or kits. The colors come out nice--I've used apple green and yellow to good effect although I've done some oranges that got specky due to my insufficient mixing. I think next time I'll hold back a teaspoon of base oil and mix the powder with that before glopping some of my batch into it for mixing and returning to the pot.
I think you should order at least two colorant options, maybe three, and possibly all four. You'll probably get at least some use from any set and more options are always better than fewer options. Oh and check out the powders at WSP too. I'm gonna order some of them tomorrow myself.