Depends how you do them and how thick. In the oven maybe 15-20mins until they are brown and on the pan on the second highest setting, I turn each side, until brown (15mims). I also check by cutting up one in the middle.

Depending on the thickness I err on the side of caution and cook sausages for half an hour, then slice open to check that they are fully cooked.

The time I cook snags is about 25-30 mins but I do mine in the oven as have to cook quite a few at a time as we are a big family.This way I do not need to turn them or keep am eye on them either On the BBQ hubby does until he thinks they are cooked, he bends one to test after 20 mins to see if cooked enough.