Can't speak for PushyDad, am sure he will post on this later, but have you looked at both schools i.e. Habs and St Albans Boys?
For us, we definitely found that spending time at the schools with our DS and also without him was the best way of deciding what school we felt was best for him. Of course, he made the final decision on which he went to as he got into both.
We felt strongly that if we were going to 'pay' for his education then regardless of location, we were going to try and get the best possible fit for him. I have a few friends in St Albans whose children also go to Habs, and they told me that the school bus service was second to none, and really 20-25 minutes on a coach to school is not a big deal.
I understand that travel may be an issue for some when they are 11, but they don't stay 11 of course, and in their teens the bus is actually good social fun and allows them to mix with both the Habs Girls, and also boys from other years.
In essence, I guess what I am saying is, we felt that St Albans boys wasn't right for our son, and although convenient travel wise (he can walk in 15-20 minutes) in the short term, we felt that the positives of Habs far outweighed that short term travel convenience.
As a friend once told me, there is a school for every child, you just need to find the best one for yours.
Good Luck with it all.