What Ideal implant size will work for me better? 340cc or 375cc? (photos)

Good day! For your guidance, here is a list of generalized breast implant sizing for most patients:
32A to 32C needs about 250-275cc
34A to 34C needs about 300-350cc
36A to 36C needs about 350-400cc 
Contact your surgeon and discuss realistic goals and expectations when deciding which implants are the best for you. Best of luck! #RealSelf100

Thanks for your question and photos.
Picking implant size can be one of the most confusing parts of breast augmentation for patients.  There are many factors involved in selecting your size.  First there is the physical limitations of your current breast.  What size is the current breast and how much skin laxity do you have?  This will ultimately determine the largest implant you could use.  Second, what is the look you are trying to achieve?  Most women say that they want a "natural" look but this can mean completely different things to different women.  Using computer generated and manipulated images is a good start.  Your surgeon should be able to provide you with pictures of women before and after breast augmentations to get a better feel as to just how much projection and fullness you want.  Trial sizing with silicone inserts is also a good way to get a general feel for the size you desire.  When taken all together your surgeon should be able to give you some guidance as far implant size.  Also, the difference between a 340cc and 375cc implant is quite small.  Just over an ounce.  Not having had the opportunity to meet and examine you in person I would likely suggest the 375cc implant.  Rarely do we have women return saying that they wished they went smaller.  Just the opposite!  It is not unusual to hear women say that they wish they went just a little bigger.  Either way make sure you have an open and honest discussion with your surgeon before any surgery.  It will be time well spent!
Best wishes.