I am learning with GT only. Mainly because I need something really flexible - I can practice anytime and have everything to hand, whatever time of day (or night!). Although a teacher is fantastic for that one-to-one, I'm doing just fine here! I play flute also, and was taught by a teacher for that. But I was younger then and had Mum as my taxi - now its the other way round it needs to fit in with me!! Theres alot to be said for learning when you are a bit (!) older too - I am so much more commited now than I was when I was a teenager learning the flute. I know when I've got it wrong, and I have the patience to get it right. I don't get frustrated, and I love practicing!
Now, if I could find a teacher who came at the same price GT charges, who is available 24/7 and doesn't mind helping me at 2am, then I'll be there!! ;)