Several years ago, I made my own version of this by stacking two LX-1000s together, both attached to a signal sensing DVDO unit, with the DVDO also carrying the audio. Then the DVDO was connected to the TV set and amp via one set of cables. To get it to work properly, I'd load the two discs, usually a title with side 3, sometimes 3 and 4, then turn off player two, and start player one.

The disc would play through sides 1 and 2 with all functions available. When it was done, I simply hit the power button on the remote. Player one shut off and player two turned on at the same time, and the DVDO switched over to player two in a flash automatically, so the title would continue. Of course, this only works well if you have two players that are basically the same with the same quality output, and a unit that will automatically switch the A/V signal to a single output.

Some of the industrial models have control setups to allow ganging them together. For example, if you have serial control on a couple of LD-V8000s, you can assign each one a unique ID, & send strings of commands to each one telling it what to do. And they can be slaved to a master sync source, so if you also have a serial-control switcher, you can cut from one to another without a single frame's delay.

Was there a UK/Europe version released?

MSB was planning a dual disc player that I detailed here: MSB LS-2 Platinum Dual Transport?

It is assumed that they were upgrading a Pioneer LD-W1 for this, but no one can be sure. The article blurb there from Widescreen Review does say that it is a CD/LD transport which the LD-W1 isn't (plays only LDs), so this might not be the case.

Yeah, side changes are substantially worse on the W1 than any other player by a mile. It depends on what side you are on and where you are headed but I think Side 2 to Side 3 is the slowest.

Mine recently broke (!) and I haven’t had time to look inside.

That’s not the right remote.