Hello,
Depending upon the patient's preference for a particular aesthetic, either could be more appropriate, and therefore better. However, when it comes to long term durability of results, and minimizing poor outcomes (complications), lower profile implants (Style 10 or 15) have a better track record. High profile implants (Style 20 or 45) have a high risk of causing unpredictable outcomes like excessive tissue thinning, drop out, double bubble. etc. Additionally, there is a common misunderstanding about what a high profile implant does, namely that It gives upper pole fulness more than a lower profiled implant. The reality is that it might or it might not, depending on particular factors. In some situations, you might have LESS upper pole fulness with a high profile implant compared to a lower profile implant. What a high profile does consistently is give more projection, and that's it.
You should have a few consultations with reputable surgeons in your area (NY?) that perform all types of cosmetic breast surgery including implants, lifts, reductions, and revisions of all the previously mentioned. These surgeons will be certified by the ABPS and more than likely members of the ASAPS as well.
Best of luck!