When I purchased my TN75F, I wasn't aware of what super steer was. I probably would have passed on it if given the choice. That being said, I wouldn't be without it now. In the middle of my gardens, I have a cleared flat where I mix my compost piles. When I designed the space, it was based on my chore tractor, a Yanmar 240D. I normally work with 16 to 24 foot piles and it gets cramped for room when we are shredding hay (often 50 or 60 bales at a time). The super steer allows me better access and manuverabilty than my little Yanmar. With a bucket about three times the size, that makes short work of that job. The super steer also allows for easy manuverability inside our fenced areas and snaking around between trees and other equipment.
I think it's great, but any technology like super steer should be an answer to a specific need. We have a machine shop and our steering is just about due for overhaul (RickB estimates about 4000 hours). While not a overly demanding job, it's not one that most home owners would be comfortable with, so the cost of overhaul should be considered. Having it if you don't need it will just result in eventual, unnecessary costs.