I have 650cc HP silicone implants. I’m switching them to 800cc silicone. Which brand should I use? (Photo)

This may not be what you want to hear, but based on the photos, I would not recommend changing from 650 cc to 800 cc period. The brand is not the issue, and neither is the profile. If your goal was very big breasts, you have already achieved your goal. The breasts already look as if they are touching without a bra on (usually there is a space between breasts without a bra), the side-boob is to the degree that the implants stick out in the path of your arms, and there are stretch marks on the breasts. There is only so much your body can handle. The only thing I see happening by changing to 800 cc is further pressure and damage to your skin and natural tissue, including potential pressure deformity of the underlying ribcage, possible worsening of the stretch marks, greater degree of breasts touching or symmastia (uniboob), more dramatic side boob, higher risk of drooping more quickly, and overall a greater risk of problems. An in person exam would be required for an accurate assessment (photos are helpful, but do not take the place of an exam) and recommendation, but I would really advise caution when considering that large of an implant. While beauty is in the eye of the beholder, sometimes the risk simply outweigh the benefits. I feel it is our job as plastic surgeons to make sure our patients are safe and educated on their options, and avoid procedures that carry a high risk of complications.

Dear mallorynunez28,Implant profile is a very important consideration. Many patients wrongly assume that the higher the profile the better. The truth is, the more profile (or projection/height) and implant has, the narrower its base has to become. This has several problematic consequences. The first is that the patient loses width and therefor cleavage of the breast. The second is the breast becomes more narrow and pendulous, often falling lateral and onto the side of the chest, and third, high profile implants have a higher risk of bottoming out because they exert more pressure on the inframammary fold than moderate profile implants. High profile implants do have a role in symmastia repair (when I need to narrow the basewidth) but otherwise I try to avoid them.Daniel Barrett, MD, MHA, MS 
Certified, American Board of Plastic Surgery  
Member, Am. Society of Plastic Surgery

Thank you for the question.  All of the FDA approved breast implant manufacturers provide good products. Each of the manufacturers will use different terminology when it comes to describing their breast implants (and each will claim that they have the "newest" and "best" breast implants).  
Personally, I think that careful selection of plastic surgeon and careful communication goals are  the two most important "factors" when it comes to achieving the desired outcome with breast augmentation surgery.  The specific breast implant manufacturer and even type of breast implant are far less important factors, in my opinion.In my experience, many patients looking for the "extra large" look, are disappointed with the use of 800 cc silicone breast implants (and achieve their desired outcome utilizing overfilled saline breast implants).My best advice: select your plastic surgeon carefully. Make sure that he/she has significant experience achieving the types of outcomes you will be pleased with. Then, communicate your goals carefully, as  well. Working together you will come up with a good plan to achieve your goals.  
I hope this helps. Best wishes for an outcome that you will be very pleased with. 

 800 mL implants are made by two of the three manufacturers used in the United States. Both Mentor and Allergan have those size implants. Sientra does not. I use both Mentor and Allergan and don't have a huge bias when it comes to smooth versions of either implant. Hope that's helpful.