I use my keyboard most day for between 6 and 12 hour , sometimes longer , and this keyboard be the best that I have use on a computer . it give positive tactile feedback without be really click-y . it be quiet without the key be mushy . in short , it be a really good keyboard , and great for the money . I buy this one to replace my previous one -lrb- the cat dump my glass of water over it -rrb- , and after use another keyboard for a few month . the other keyboard never feel right or good ; this keyboard , conversely , just `` feel right . '' the initial natural ergonomic keyboard 4000 I purchase a few year ago replace the original putty-colored Microsoft Natural Keyboard I have use since 1996 . 10 year be about the most anyone can ask of a keyboard , but have I not want to change over to a native usb connection , I would likely still be use it . this keyboard be nearly perfect , save one annoyance : the space bar . there be instruction and video that describe re-bend the metal bar under the space bar to make it more even , which I think would help . all in all , I do not think you can go wrong with the natural ergonomic keyboard 4000 .