Levels and reviews are useful as one part of your assessment as a buyer.
I always recommend that buyers start out with a low cost gig from any seller they haven’t dealt with or weren’t referred to. It’s rare to see a TRS scamming, but not impossible. You can always report them to Customer Support.
One of the things that makes $5-10 gigs so important is that buyers have a chance to try something cheap before committing to more money. When you order a $5 gig and you don’t like the results, you can either ask the seller for a refund, ask Customer Support to mediate (if the seller says no) or you can lose the $5 and gain the right to leave an honest review for the seller. At least it’s a small price to pay for both a test and a way to warn others.