The overall design is very clever and sleek, the storage with good locking and closer is really good. However, the biggest difficulty is that the operating switches are almost continuous with the shape of the barrel and often difficult to find by feel without looking. A few tactile clues would be very helpful in the next design, and different feel for forward and reverse would be ideal. Remember that the user is probably holding something in one hand, concentrating on getting a small screw in an awkwardly located hole that is barely visible while being bent at an uncomfortable angle - not the time when you want to have to look for the switch! Also I found that despite all the tips, there often wasn't the ideal one. A few really long tips would have been useful, for example.