Embrace your insanity and go for it.
I now own the Tessar 75/3.5 MX-EVS and the Xenotar 80/3.5 E2. I also own a Yashica Mat 124G. Nice camera but it does not compare to either Rollei.
My advice is to buy whichever is in the best condition. They are all very good cameras so condition will mean more. Whatever you buy send it on to Harry Fleenor to look it over for you. He also sells a small pdf e-book that provides great information to help you with your choice.
Finding Your Rolleiflex
My personal favorite is my Rolleiflex K4B 75/3.5 MX-EVS. It is compact, light and very easy to handle. It doesn't have a lot of extra bells and whistles but it is a very smooth camera to operate.