But it really depends on what you want in a 'table. If you're going to sit in the dark in your sweet spot and get all tingly at the 3-dimentioal sound stage spread out large in front of you, then I'd go with the the Rega. OTOH, if you like the looks and pedigree of that particular vintage DD 'table, and you'd enjoy interacting with it (The Rega really is just an arm stuck on an MDF plank with not automation and no adjustment to think of) then go with the Kenwood.
What's the price difference between the two you're looking at? The Planar 3 is a $1,200 'table. Looks like there are KD-500s out there for around $400. If you can get a Planar 3 for $400, it makes it an easier choice.