Last weekend i've replaced DISA unit with new one. Blimey, it is a totally different car. original one wasn't that bad at first look, just a little flimsy flap. It seems to me it wasn't able to fully open or shut intake, so both routes, long and short was half open all the time. So, now lot more torque on low revs, and considerably more on high. 5th gear feels like 4th before. New unit seems to be aftermarket, not original bmw part, at least i dont see bmw logo on it, but partnumber is correct. Even if it is a copy, for 84 quids it is best i've done to this car so far.