TWA bought 10 727-231As in the very late 1970s, perhaps 1980 or so. TWA used the same engine, the smallest 14,500 pound version for all models of its 727s.
As I recall the MGTOW was slightly greater on the 231A (3,000 pounds I believe) because of a stronger landing gear. The other notable difference I recall was a so-called improved Sperry autopilot that would flare (but not decrab). We were authorized CAT III with a DA with this gludge. So far as I recall, no one flew such an approach in actual conditions.