We hated them. The idea of a bomber being so heavily defended that it could bomb in daylight appealed to Bomber Command, after all the B-17 could fly higher and was more heavily armed than all other RAF bombers at the time.
However, the idea was soon proved false. The B-17 could fly higher but the performance of German interceptors was remarkable at the altitude, and the B-17s could not defend themselves even in close formation.
The idea of a self-defending fortress in the sky was hashed over once again when the USAAF began their campaign over European skies. Lessons learnt twice by the RAF did not have any effect on the brains of the USAAF - which cost many people's lives. Then, finally, in 1943 they realised a long-range escort fighter would be the only way the daylight offensive could continue.