I'm using the Sigma 18-125mm F3.5-5.6 DC. I guess it serves my purpose and I do agree it's a not bad walkaround lens. Dun have to change the lens too much to my 70-300mm. I guess you really have to ask yourself if it's good enough for you or not and what is your requirement and expectation. If you want wide and tele, you can also consider the 18-200mm (tamron) though 18-125 is already good.