I commute, but not regularly. Even if I had to commute 5 days a week, I don't think living in London would be feasible for me.
I don't think i would "move out of London to save money" if I already owned a property in London. It doesn't make sense. Money spent on commuting is wasted (like rent), but if you pay a bigger mortgage (because your house is worth more) that's an investment.
The reason I commute is because I just can't afford a house in London in an area my partner would be happy to live in. Right now, he loves the house and the area we live in, our house costs £300,000 (first time buyers 18 months back). We couldn't get anything in London for that price, especially with his "requirements".
In other words, the commute was a compromise. He was/is very anti-london, unless we had loads of money for a huge house and exciting social life. Sadly, we're not on that kind of money and have no family financial help.