In May I purchased the SQ84T for $2400 (including tax). I run it on a NH TC40A and there is no issue with power or weight running on hills and rough terrain with the loader, minus the bucket, on the tractor. Eventually I will run it without the loader when I set out to cut all the fields.
However I am not entirely happy with the cut, for some reason it does not seem to cut as well on the offset spindle. My original concern with this cutter was the slow blade tip speed and I am still wondering about it. Unfortunately I have not had a chance to run it through heavy vegatation because the fields were thin when I bought it in May and this has been a dry summer so the fields are still thin.
The concept of the unit is excellent with it being a short overall package and tucks in close to the tractor making it very easy to manuver with. My TC40 probably handles it better than it would a 6' conventional. My thoughts are that this cutter will not decrease your cut time over a conventional 6' model because the lower blade tip speed results in a slower travel speed which makes me guess any cut time difference would be insugnificant. Basically I don't know if I like it yet or not.