For me, I ride with DT shifters because I like the 7 speed setup my bike came with. Yes there are 7 speed STIs out there but most of them are low to mid range and old now so could be getting unreliable. I could change to 8speed and have a wider range of STIs but then I'd have to change wheel or at least freehub body and re-dish my wheel, I'd also have to re-set my frame to 130mm which I don't really want to do. So I use DT shifters because I use 7speed and I don't find them enough of a pita to change. I don't race, I don't ride in bunches much. If I did I might want STIs enough to change to 8, 9 or 10 speed.
For me, I ride with DT shifters because I like the 7 speed setup my bike came with. Yes there are 7 speed STIs out there but most of them are low to mid range and old now so could be getting unreliable. I could change to 8speed and have a wider range of STIs but then I'd have to change wheel or at least freehub body and re-dish my wheel, I'd also have to re-set my frame to 130mm which I don't really want to do. So I use DT shifters because I use 7speed and I don't find them enough of a pita to change. I don't race, I don't ride in bunches much. If I did I might want STIs enough to change to 8, 9 or 10 speed.