Ground Zeroes was 75% PS so I expect no less as for the PS4/X1 ratio of MGSV

The majority will be on the ps4

5:1 seems to be a lot to me. I would say 3:1.

7:2 - PS4:X1
3:2 - PS3:360

3-4 to 1 or so.

3.4 : 1

Some more data to use:

Amazon.de:

PS4: 11th (Steelbook), 50th (normal)

X1: 229th(Steelbook), 506th (normal)

Amazon.fr:

PS4: 3rd (Console bundle), 4th (normal), 10th (Steelbook)

X1: 73rd (normal), 127th (Steelbook)

Amazon.it:

PS4: 7th (Steelbook), 8th (normal)

X1: 209 (normal), 250th (Steelbook)

Amazon.es:

PS4: 5th (normal), 9th (Console bundle)

X1: 105th (normal)

Amazon.jp:

PS4: 11th (normal), 13th (special edition 1), 19th (special edition 2), 23rd (honestly no idea what version this is), 204 (Console bundle)

X1: 1555th, 1556th, 2293rd, 4966th (amazon.jp is confusing)

Ground Zeroes had a higher PS3:360 ration than PS4:XBO ratio. No way the PS3:360 ratio will only be 3:2.

3:1 in favor of Playstation

I think PS4/X1 sales will be much higher percentage wise than PS3/360 sales for Phantom Pain than were for Ground Zeroes due to releasing later in the console life cycle. We shall see.