What are the differente extras between BTTF R1 vs. R4 (1 Viewer)

[GeorgeHegyi]

I had read that besides the framing problems on Back to the Future, there are different extra material between the R1 DVDs and R4.
Anyone know what extras are missing on R4?
Thanks
George.

 

[Runar_R]

R4 (and R2) gets DTS, but has fewer extras.

The differences are summed up here for each film.

 

[GeorgeHegyi]

Thanks a lot. I am going to check them right now.
George.

 

[Mark_Wilson]

There is also an R3 Korean NTSC DTS version of BTTF too.