Got my VL45Pro S a coupe weeks ago.
Fits my second hand Dometic slide perfectly. Tray dimensions are exactly 29.125" x 16.125".
Ran a few complete cycles on my Yeti 1000 Core and then decided I was keeping it, so I siliconed all the seams. I taped them up to get nice lines. I would probably only bother taping the two short vertical seams on each long wall and the drain plug next time. I cleaned/degreased the seams a little and then used GE all purposed silicone, smoothed out with a gloved finger. The silicone cures fairly quickly so be sure to pull any tape immediately so you don't have to touch it up.