I have used bio oil. Its true stretch marks never disappear, but i definately noticed a difference in how noticable they were after using it for about 3 weeks, rubbing it in every evening before bed.
So if you'd rather not bother less its gong to make them disapear, dont bother with it, but if you'll keep at it for a bit, and would be happy with an improvement, then give it a try.
It makes your skin look good too!
Boots have a promotion on Bio Oil at the moment which makes it more affordable, or you could do as i did, and buy a big bottle on ebay at a very good price.