I have about 2000 hours in the 727 at FedEx. we had a whole bunch of different variants the -100 would actually go faster and was a little nicer to land. The Valsan conversion was on a handful of our planes and I still fondly remember flying one empty from Ohara to Indy (non stop).
This plane was awsome in all loads but with a light fuel load and no cargo it was a ROCKET SHIP I was right seat and it was my leg so I prebriefed the takeoff because if I didn't go 25 degrees nose up on takeoff I would have to pull power to keep from overspeeding the gear or flaps. 20 miles from the airport at 20,000 feet! most impressive and really a lot of fun. Landing it empty had its own set of challenges and usually resulted in some moments. The key was to be on speed on approach and get the power back just at touchdown. Normal technique was to pull the pods back to idle at about 20-30 feet and then close #2 just at touchdown. Navy training had us always on speed for the approach...
Quite a versatile airplane, noisy cockpit.
Sparky