I've shot an RX for years and recently acquired an RTS and RTSII finding some good bargains. The 85/1.4 is hands down my favorite. Awesome lens. But the right hood can be hard to find as us expensive now. The 50/1.7 my next fav. The 50/1.4 has better build quality but is now so expensive as to not really be worth it unless you absolutely need that extra speed and will shoot wide open a lot. Tests online report both as great performers with the 1.7 having a slight edge overall but only barely. Next fav is the 180/2.8, such a beautiful lens. The 100-300 Vario-Sonnar is one of the sharpest lenses I think I've ever shot but its so big I do not use it that often. The macro 60/2.8 is up there with the best of this type for sure. I also have the 35/2.8 PC which is a true marvel of quality build and workmanship and is a great performer though its expensive and quite big and heavy. Only lens of the Contax Zeiss set I've ever sold was the 80-200, good but not the stand-out the rest have been. And the 50/1.4 when I determined the 1.7 was as good or better. Now I was lucky, I got all of mine mostly back in the late 90's early 2000's for about half what they are going for now (before the digital crowd discovered them once good and cheap adapters were produced) but many are still quite nicely priced. Back then the 50/1.7 could be found for under $100 and the 1.4 for only a tad more. Now the 1.4 is often $300 or more. Another reason I sold it since I had the 1.7 also, no regrets.