I had one for years, when I was shooting a lot of film at airshows. Worked great on my old Minolta bodies, X300/700. As they had one of the best/brightest view finders. Then on my Contax I would change the focus screen to a plain one. As the split image would black out at the F8 value.
Thing is if you use one on a modern Autofocus camera, they tend to loose light to the viewfinder as it is split to the autofocus sensors. So manual focus would be a bit slow and tricky.
Plus Tamrons require the interchange amount to fit, so be sure you can get a mount to suit what ever body you have.
Lovely lens having said all that .... should be dirty cheap now.