My first thought when I see someone come on here and start a question already knowing what size implant they want and how it should be positioned is: How do you know that? The operation of breast augmentation has truly become quite a complex thing, and although the technical exercise of merely putting in breast implants is pretty basic and something most plastic surgeons could probably pull off, in order to obtain reliable, reproducible, and lasting results time after time, that are truly beautiful and aesthetically correct, a surgeon must really understand the nuances and fine points of this operation. And this is never more true than in the case in which a lady specifically requests a "natural looking" breast and she is thin. It is very easy to make a thin woman's breasts appear "fake," too round, disproportionately large, improperly positioned, and on and on. I like to tell people that of the money that they pay me for breast augmentation, 10% of it is for what I actually do, and 90% of it is for knowing how to do it well. You are correct that there are many different "styles" of breast implants available to us now, and there are many different sizes within each style, and there are also 3 different manufacturers approved in the US to sell breast implants, each with it's own subtle differences in gel types, outer shell technology, texturing, size ranges, and dimensions. In order to get the optimal result for each individual person, a surgeon must not only understand the differences between these choices and how to exploit those differences to select the best one for each patient, but he or she must also understand the technical nuances of planning and executing the operation. Many surgeons don't even understand these things, thus, I don't expect many patients to either. This is why I ask how you actually know for sure what it is that you want as far as implant size and location of placement. If you do, then you should at least discuss it with a surgeon who can validate your goals. The best advice that you can receive here is to keep an open mind about the actual plan for HOW to best reach your goals and focus on the specific things about your breasts that you would like to change. Focus on sizing for appearance from your perspective and let the surgeon work out the actual volume, style, and dimensions of the implants to best meet those goals. Schedule one or two consultations with board certified plastic surgeons who have experience with many different types of breast implants and techniques and who can properly evaluate you and guide you to the best option to reach your goals. This is the way to maximize your chances of getting the results that you want and eliminating as much of the "guesswork" as possible. Good luck.