I purchased my Shape Ups approximately six months ago.  From day one I put them on and found them to be comfortable, lightweight and without difficulty walking.  I have always had muscular legs but within two weeks the cuts seemed even more define.  I personally did not have a need to remove them after the approximate recommended hour, they felt that comfortable.  They truly do what they profess to do especially in regards to upper thigh, buttocks and legs!  I must say that spring had come and I needed to do mowing and other lawn work and thought no big deal in keeping my Shape Ups on.  I did this chore for some few hours.  Maybe I over did my workout in them especially for doing tedious lawnwork, because my left hip was throbbing and achy.  It is also possible that I got laxed in the walking motions they tell you to utilize on the DVD.  On the other hand it is possible that they were working some muscle groups that havn't been worked out in a while and this was my bodys way of saying it, you know when havn't worked out in awhile and you start an excercise program and can hardly move the next day?  I will have to determine whether my Shape Ups need to sit out the lawnwork job and just use them for everyday walking.  To myself they were well worth the cost, and when I say that I have never had a more comfortable lightweight shoe I am not exagerating.  Your purchase will definitely not be a disappointment and you will surely see results from the waist down without a doubt!  I love them!