Hi Happy Wanderer.
I was in exactly the same situation about 5 months ago, as I had planned on going to London Met to do the ATPL while at the same time thought about BGS.
I ended up making the decision of going for BGS for a number of reasons.
1) I could start the course when I wanted rather than when the full time school started.
2) I could work at a pace that suited me again rather than what the full time course did
3) I could work from home and fit my hour building in around it. IE if the weather was good in the morning, fly then study in the afternoon.
4) The time scale of Distance learning means that , working hard I can have the 14 exams sat in 5 months rather than the 8-10 months the full time courses give.
Having just sat the mod 1 exams for BGS I can honestly say that I made the right choice, the course with bristol was 1st class, Alex and all the teachers there really know their stuff, and I mean really really know their stuff. The back up and support is fantastic.
Although the 2 week refresher course was Bloody hard work, it was great fun and Tom who takes the Flight planning classes is an absolute legend, If I don't remember anything else I will remember his stories...
The way I see it is, If you want an airline job bad enough then you need to work hard, BGS supply you with everything you need to suceed, so all you need to do is put in the effort and you can't but not do well.....
How have I and am keeping focused? It's my money & my future that I'm putting on the line, that's enough for me.
And in hindsight would I have gone another route? Absolutely not.
The bottom line is you have to do what is right and best for you but what ever that is make sure it's 100%....Good luck either way.