Might not help you. I have recently had a mastectomy but chose not to have implants. 
 

Previously however I have had 2 sets of implants prior to my cancer. 
 

I had tear drop in 2012, and July last year I had round. 
 

I noticed the tear drop ones sagged quite quickly and didn't end up being a great shape long term. Obviously I didn't get a chance to see how the round would end up, but went for the round implants on recommendation from cosmetic breast surgeon. Hope that helps x