I hate mine- I am a size 8-10 but my upper arms are flabby- not so much bingo wings as jelly bags and the inner side ( not the back) of them was all dimpled and wrinkly .
HOWEVER for 2-3 weeks I have been doing half press ups, tricep dips and lifting small 2 kg weights- roughly every other day- and i can see a difference already.
So- there is hope!