Things to Look for When Evaluating Encoders
"Our encoder mixes DCT synergies and gamma radiation to provide excellent quality that abides by industry standard salsa dancing techniques, using adaptive streaming techniques." — Vendor.
First, verify they actually have a product to sell that actually exists and can be tested in-house.
Warning signs: incredibly vague descriptions of the product, lots of "patent pending" claims with no real patents to be found, and insistence that they can do the testing for you and provide metrics instead of letting you test it yourself.