DS was going down in my bed, then I'd put him in his bed til his first feed, then in my bed again. He was waking 3 - 4 times a night.

About a month ago I started settling/feeding him, then putting him straight in his bed while still half awake. He started sleeping til 5am by himself. This morning it was 6.

He sleeps in his cot, with no blankets most of the time. He refuses to sleep with a blanket on. FUN!
When he's sick I don't bother with the cot at all.

Have you tried putting a bumper around the cot? It could help. I've had DS sleep on his fold out couch when we are away from home. I've got one with a zip on blanket so he can't wriggle off.