Services such as $interval or $timeout are very simple - $http is also a fairly simple service to replace too. I don't really view it as much of an issue when i

Services such as $interval or $timeout are very simple - $http is also a fairly simple service to replace too. I don't really view it as much of an issue when it comes to lock in or migration, there are usually far more perilous pitfalls when it comes to lack of being able to migrate, such as bad app architecture or hacks.