One thing to consider that hasn't been brought up... The 19/66 has a longer cylinder than the 27/28. This fact will allow you a certain amount of additional flexibility when loading heavier, longer bullets such as the Keith / Lyman 358429.
I wouldn't worry about longevity. The KT-357 will likely out last you.
This PD trade in 66 has a documented round count of over 10,000 rnds of Federal 125 Grn. JHP's.
I knew the Officer that carried it, and that it was above average in accuracy so I held it back for myself when it came in for trade against SiG226s.
I replaced the hand and cylinder stop when I round butted it, and have shot another 1,000 or so rounds through it since...
Drew