Hmmm... That's an interesting one!!
I do not dare be 100% of any of them. But all in all it looks like a genuine thing or either VERY good forgeries! ;All the elements that usually uncover fakes are correct, but there are some other things that draw the eye.
Roger's looks the weirdest - the 'R' is totally wrong for example, but on the other hand there were times that he DID strange things to his sig.
(If you see the sig he does NOWadays...!)
Brian - looks authentic at first sight, but some details are strange: there are some unusual 'curves' in there... The rough shape of the autograph is how he did it round early 90's - though the curves indicate it might be older...
John - I'd say it could be genuine, but not 100%
Freddie - Hah! Again this one is a bit odd - but still very possibly genuine. I'd say this also should be a bit 'older'... The d's and the 'y', make one think - but it's very possible that Freddie did it that way (signed standing, or in a hurry??)
Let me guess: this is your personal copy - you got John's signature late 70's, Freddie a couple of years later (very late 70 or maybe early 80's), Brian's in 1993 and Roger's last week? :-)