We have been known to do well in both departments at the same time... Alan Fettis? I was very much a kid when he played but i loved him. Bo Myhill deserved honourable mention. Was a quality goalkeeper at the levels we played with him... lower PL was about his level. Stockdale - decent championship GK. There's better in the championship than him (Schmeichel being one that springs to mind). £4mill was laughable. Terrible on crosses. Guzan - I didn't really want to sign him when we were in the championship. Mannone - fantastic goalkeeper who I would love to see back here one day. If Sunderland go down, he won't be short of offers I'm sure. McG - best of the lot that I've seen at City. To me, the reaction save against Chelsea was something else. Although on TV, didn't look as good as real life. He doesn't have any clear flaws to his game that can be punished by opposition.
It would be as replacement for Lindegaard I would have thought. Other than him the only keeper they have as cover for De Gea is Amos. (based on looking at their cup squad, they've presumably got about 18 other keepers about to break through as the next big thing)
McGregor by far the best goalkeeper in my lifetime. Myhill get's a special mention, as does Mannone. Stockdale was good, but as with Myhill, struggles to command his area at crosses.