I've read some RS reviews and some intramuscular butt implant patients say their pocket has stretched out and implants are now shifting and rotating. Do they really stretch out? They're saying it started happening 10+ months after surgery. Why does this happen & what precautions can you take to reduce this risk? Do and/or why do oval (not teardrop) have a high risk of rotating? Really want intramuscular oval but can't make it out to the west coast for surgery. Any info greatly appreciated!!