I used to ride with Draggin Jeans however switched to pants also with knee armor (and then knee + hip armor) after reading that relatively few riders slide on their bum Vs hitting their hip or knee on the ground when involved in an accident. However knee armor in some pants does tend to make them ride up legs. Also if you ride a cruiser then you may find in winter wanting your pants to sit down more or want your rain suit to sit down as feet forward means wind up the pants.
The BMW City pants I have ride up the legs very bad. No idea why as the armor is adjustable and I have tried it in all positions and comfortable in any position but the legs just want to ride up and sit at the top of my boots. After my last ride to the New England Tablelands with the colder air chaffing my exposed lower legs I decided to try find a solution as the pants are otherwise very comfortable and seem to be perfect fit.
I obtained these clamps/straps very reasonably priced from eBay (look awhile before buying - the prices vary wildly) and tried them out last ride. Happy to say they work perfectly, they did not intrude yet held the pants in place. They are adjustable for length and the clamps held fast all day yet do not a fix in a way to damage your clothes. Living in the tropics I only see myself wearing these on the odd cold days but for a couple of dollars it really makes a difference to my comfort on cool days where I would not don my full winter gear but don't want cold morning air circulating around the tops of my boots thus making my lower legs and feet cold.