Breast Augmentation Redo - Will 50cc Make a Difference?

I have found that it takes at least 100cc to make a real difference that both patients and surgeons can see and are happy with

Yes, it is likely that you will see a difference with about 50 cc increase in breast implant volume.   The much more important question with be: will  this increase be the correct choice when it comes to  achieving your desired outcome when it comes to breast size/shape/symmetry…?  Anecdotally, I have found that most patients who wish to "upsize" their breast implants benefit from at least a 100 cc increase in volume. Sometimes, additional maneuvers such as adjustment of breast implant capsules are also necessary to achieve the desired outcome.  
Generally speaking, the best online advice I can give to ladies who are considering revisionary breast augmentation surgery (regarding breast implant size/profile selection) is:
1. Concentrate on choosing your plastic surgeon carefully.  Concentrate on appropriate training, certification, and the ability of the plastic surgeon to achieve the results you are looking for. Ask to see lots of examples of his/her work.
2. Have a full discussion and communication regarding your desired goals  with your plastic surgeon. This communication will be critical in determining  breast implant size/type/profile will most likely help achieve your goals. 
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 or D cup” or "much difference" etc 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.   
3.  Once you feel you have communicated your goals clearly,  allow your plastic surgeon to use his/her years of experience/judgment to choose the breast implant size/profile that will best meet your goals.  Again, in my practice, this decision is usually made during surgery ( after the use of temporary intraoperative sizers).  Viewing the patient's chest wall in the upright and supine positions, with temporary sizes in place, help select  the best breast implant size/profile for the specific patient.
 Best wishes. 

To begin with the 25 cc difference you were concerned with is less than a shot glass worth of volume (30 cc's). Your breasts will change more than this with weight fluctuation, hormones and time. Waiting a full year would be a great idea. My concern is they you have realistic expectations and realize that plastic surgery (and life for that matter) is an inexact science and art form. Focus on the big picture.Here are some general considerations in choosing the best implant size:It is very difficult to determine the exact size and shape of implant that will fit your frame without an examination by a board certified plastic surgeon. This is because several measurements not to mention your breast characteristics are needed to determine the optimal implant size to obtain your goals. Without knowing these dimensions it would be tough to answer your question. For example your native base width of your breast will determine in many cases the maximal volume per implant profile that you can accommodate. To illustrate a 100 cc difference may make a significant difference with a narrow base width, but much less of a difference if you have a wide chest wall and wide breast “foot print”. Additional critical decisions will also be made by your plastic surgeon such as: whether your implants will be above or below your pectoralis muscle. These choices are recommended to you based on the look you desire, the amount of sagging you may have, and other deciding factors. I always find it helpful for patients to bring in photos from my or other plastic surgeons’ websites to illustrate what they would like to look like. I bring these photos to the operating room for reference during surgery so that I have the advantage of “seeing through my patient’s eyes” to achieve their wishes.I personally order more than one set of implant sizes and use sterile sizers placed in the pocket during surgery to know in advance exactly which implant would work best for you. Software morphing programs can be helpful in some but not all cases (e.g. doesn't work well in my experience with existing implants, sagging or asymmetric breasts).My advice is to accept advice from your board certified plastic surgeon after a formal consultation and examination with measurements.. If still confused don't hesitate to get a second opinion.