I got 700cc uhp now I was wondering if 800cc would be a bigger difference? If it is worth it to later on change to 800cc ?

Whether or not you will benefit from the use of larger breast implants, will depend on your physical examination and your goals. Of course, the use of 800 cc implants would create a noticeable difference;  the main question is whether it will achieve your goals. Best to communicate your goals carefully with your plastic surgeon; in my practice, the use of goal photographs are very helpful. You may find the attached link, dedicated to larger breast augmentation outcomes helpful to you as you learn more. Best wishes.

Thank you for the question. I totally agree big implants can mean big problems. Having not seen your photos of how large your breasts are it is difficult to comment. There will come a time where u want to down size and that can take multiple procedures including breast lift more scars. There would be some difference however not that much in my opinion. I would strongly recommend for you to discuss this with your board certified plastic surgeon.  I hope this helps.