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As far as I know, the optical formula is the same as that of the CF and CFi/e 150mm lenses. Thus, an excellent lens. Getting the compur shutter repaired if it brakes down might be a problem since spareparts are in short supply.
Just make sure, before you buy, that the shutter is working fine, maybe it even comes with a warranty.
Recently I paid 175 euro's for a 120mm c t* and 225 euro's for a 100mm c t*. Don't know what the price of the 150mm is but I would not pay much more than these prices.
In addition to what Frank says it is fair to say that the C T* 150mm is every bit as good as the CF version - excellent. Before I bought my CF150mm I trialled a C T* 150mm in very used condition and it produced wonderful images.
Only you can judge the focal length and how it appeals to what you see and how you like to shoot - it's (CF 150mm) been the very last lens I added to my kit and I'm very glad I decided to buy one - relatively compact and easy to use "on-the-go". So for greater convenience I use it instead of my CF 180mm (magnificent lens), which I still prefer for portraits and compressed landscapes. So each of the 2 has its special place and use among my kit.
BUT, IMHO the C lenses are awful to use from an ergonomic point of view - rather unappealing to hold and use to the touch and the aperture ring is unpleasant and annoys me with the EV coupling that one must override (rather than the CF convention where you must engage it deliberately). So when I found a mint CF 150mm at a very attractive price I bought that.
Funnilly enough, I have a different opinion of the C lens ergonomics on the 38mm Biogon - I really like the scissor aperture DOF mechanism and prefer that version to the CF SWC cameras.
But my negative comment about the C T* lenses is only a subjective personal thing and if you have used one in the field and are happy with it, the cost saving should / would be very substantial (proportionally).
While C T* lens parts are no longer made I understand that support for these is very readilly available - but others will be more accurate about that especially in your own "backyard".