He was maximum world class for 5 years, and that is debatable. He was never the best in the world though.
I'd say three. Maybe four. 14/15 he made a lot of good saves (actually at the time, saves you would think 'wow, I don't think other keepers would'
Can't remember how 17/18 was for him as a season as it's now a blur those few but I'd say he was easily as good as neuer (where his saves and his pros easily outweighs his negatives)
The funny thing is I remember when ddg came to us, one of the things I liked was his passing / kicking and taking chances (he was doing bloody Cruyff turns to get away from attackers)
That all seemed to go away (I guess cos he was told to just hoof it every time the more negative our manager got)
One thing I never understood from Ole was him wanting to play out the back, he didn't want smalling for this reason , bought awb and persisted with ddg for too long, but that's a different story...