Thanks for the welcoming replies.
I had to take the legs off the IKEA BESTÅ TV Bench as the 20" PVM was causing it to bow under its weight and not at all helped by the insufficient/flimsy center supporting leg the unit includes. I did originally mean to go back to IKEA to pick up 2 more of the more robust leg stubbarp’s to use in the center instead but I just don’t see any need anymore.
There is still plenty of room for a MEGACD, I could just swap the Megadrive to the location where my PS1 resides at the moment or as others have said just stack it on top of the PVM, though I’m not so keen on that idea.
That said in my previous place I didn’t have as much room to spare and I had to do exactly that! (See below:)