I have a Pfaff 2054 that has the IDT and I leave it engaged 99% of the time - I just love it - especially when sewing clothing, I know I am going to get good, even seams. My Brother Sew/Emb machine (from Walmart) doesn't have it and I notice the difference but it is still a good little machine. I just choose my machine preference for whatever it is I am making.