The Parkside says: "Includes 2 additional tool holder sections for more mou nting options"
Otherwise, they seem fairly similar. A few reviews of the Parkside in the p ast have read quite well - expressly comparing against the Evolution. But t he Evolution does get good reviews at Screwfix.
Evolution 800B Mitre Saw Stand with Extension Arms (48911) £49.99
Parkside Universal Tool Stand £39.99