Are 300ml Saline Implants Appropriate Size?

The more breast surgery I do the more I realize that there is no correlation between the size of implant and resulting cup size.  This may have to do with several factors including: the amount of breast volume the patient starts with, the shape of the patient's chest wall (concave or convex), the type and model of breast implant selected (saiine/silicone  and low/moderate/high profile), bra  manufacturer variance  in cup sizes, the  degree  of filling of the cup  with breast tissue,  and the subjective differences in patients perceptions of cup size. 
If revisionary surgery is decided upon, it will be very important to communicate your size goals with your surgeon.  In my practice, the use of photographs of “goal” pictures (and breasts that are too big or too small) is very helpful. I have found that the use of words such as “natural” or “C cup” or "fake looking" means different things to different people and therefore prove unhelpful.
Also, as you know, cup size varies depending on who makes the bra; therefore, discussing desired cup  size may also be inaccurate.
I use  intraoperative sizers and place the patient in the upright position to evaluate breast size. Use of these sizers also allow me to select the press implant profile (low, moderate, moderate plus, high-profile) that would most likely achieve the patient's goals. The patient's goal pictures are hanging on the wall, and allow for direct comparison.
I have found that this system is very helpful in improving the chances of achieving the patient's goals as consistently as possible.
By the way, the most common regret after this operation, is “I wish I was bigger”.
I hope this helps.

Another option you could consider is thte use of fat grafting to the upper pole to achieve selective fullness without a lift or larger implants.

Are 300ml Saline Implants Appropriate Size?
Hello, thank you for taking my question! I recently had B.A., 300ml mod profile saline left, 315ml on the right. My BWD was 11. It seems like my breasts have good projection, it's just that they seem saggy still. Could my plastic surgeon gone bigger? I know that BWD is key, it's just that I wanted more upper pole fullness.How can this be achieved without having a lift? I know the enemy of good is better, so I am reluctant to have another surgery. Your thoughts?

It is very difficult to comment without photos.  But if you were sagging before the surgery, without a lift you will still be sagging.  You could have gone bigger, but you would have to go with a more projecting implant to keep the base diameter without your range.  A higher profile implant would also give you more upper pole fullness.

Hope that helps.