Chose between DCD771 and DCD730. 730 is lighter, which is felt in direct comparison, while working, you don’t feel the weight of 771. Regarding the breakdown - I sin on the store . The service center refused to repair, indicating that extraneous sounds are not a defect - the cartridge works. The crunch disappears when the cartridge is fully tightened and then unscrewed. Not nice. Regarding the choice of 730 and 771: pluses 730 in a 30-minute charge, the price is 1.5 times higher. There are no more benefits. So in terms of price / quality ratio, 771 wins. For professional use and justification of the price, it is better to look towards 790. The price is 2 times higher. Advantages: brushless motor (claims 40% more run time), more powerful 2Ah batteries, 30 minute charge, metal cartridge, normal backlight (LED at the bottom of the handle).