Capnkirby.com has a review that focuses on MepisLite's usefullness on older machines. They like what they see, but not quite happy with the business model!
The review concludes that:
Quick, stable and highly usable come to mind as the easiest manner to describe what Mepis has created here. I hesitate to wholly recommend it as it is destined to be a for sale only product living outside the world of GNU. It is a great piece of work that delivers on what it has promised, but I am uncomfortable with a product such as this being for sale only, and not being available in an un-supported version as well.