Not getting into an argument over KC135 vs 707 since I have flown both, but the FAA issued me a 707 type rating based on my flying the 135. The systems are very different, and the 135 is both shorter and narrower than the 707-320Bs that I flew, but they fly pretty much the same. The biggest difference is in the landing. The 707 has slats that the 135 does not and touches down at a much steeper deck angle. My first few landings in the 707 were interesting to say the least. At least I was flying freight and Mr. Box doesn't complain about firm touchdowns.