I don't have any good answer for you about this, it is a difficult call at best. the bird does need to be able to fly well enough to keep it from getting hurt if it falls from a perch or some other place that is high up. But flying also requires a lot of visual acuity that this bird does not have and that places the bird at risk for injury everytime that it does fly. I would think that speed is the biggest issue as the risk of injury increases dramatically the faster the bird flies. You might want to try to let it fly if you can keep the flights short enough to keep the speed down which is very hard to do with such a small and fast little bird.
While this does not give you any answers I hope that it will help you to make a choice on your own. Good luck.