When debating between 2 implant sizes that are within allowable limits for my body, should I err on the side of the larger size?

There is blunting of the size when placed inside, and it may be advisable to select a slightly larger implant.  I would search for the board certified plastic surgeon who you
feel is most likely to give you
the best results. Look at reviews and before and after pictures on that
surgeon's website. Kenneth Hughes, MDLos Angeles, CA

If you try on sizers you will have a better idea of what they are going to look like after surgery.  The sizers typically look somewhat larger than the implants at that volume, so it is usually safe to go a little larger, like you had suggested.