I had smooth silicone implants-325 cc 18 months ago. Too large and low for me given small frame-5' and 90 lbs. Am considering replacing with 225-250 cc, and raising implants 2-3 cm. I heard that with higher placement - given that pocket is bigger than new implant - it's hard to get even, rounded line at bottom of breasts, and one breast may end up higher than other. Is this true, and if so, are there recommended surgical techniques to ensure symmetry & internal support with higher smaller implants?