It’s about what suits your hand/technique, your clientele and your salon image/branding
If you plan on doing intimate waxing you may want to go with a brand that promotes the results for this treatment. If you plan on doing mainly facial waxing you may want to use a “brow” brand’s wax. If you plan on doing body waxing, are you cheap and cheerful or will your clients pay extra for an eco product or a luxury branding?
If you’re going to use the wax that sets hard on the skin you may wish to use a posh brand if that suits your business. You need to consider demand, whether staff will need training (most upmarket brands require you to train to learn the best application techniques or their brand “style”) and the cost, including the cost of ordering a product in small quantities and having to pay for postage.
If you want to keep costs down, it makes sense to buy through your main wholesaler so that you can add wax to your bulk order and save on postage costs. The big wholesalers often do discount days when you can stock up, whereas the Independant wax brands only do deals once or twice a year.
There is no “best” wax, only good service and indifferent service!