ellen, I am not a student nor am I influenced in any way shape or form by any flight school.
Which school is the "best" is up to your son. Which is the better 'personal' fit is more important. Both produce a pilot with a CPL, IR, ATPL subjects completed.
Doing a degree along side a full time MPL (or whatever) is unbelievably tough. Personally, I'd ask myself what I want to do with a degree. I'd do a degree or a trade (electrician etc), gain some experience and money and then go full time - if that's still the goal. Growing up is very important + understanding what earning an income means.
If your son desperately wants to fly for an airline in the UK, then the best bet (sadly) is to do a tagged scheme. That is, the airline already has tagged the candidate. Note, there are NO guarantees what will happen between contract signing and strapping himself to an aircraft.