Afraid of getting the fake look and want to stay as natural as possible. Are Mentor boost implants the right choice? (Photo)

I’m looking to get my breast redone real soon. I’ve had my sailing implants pictured above for 20 years and want to replace with silicone. I am high profile currently but want to switch to mentor moderate plus so my breast sit a little closer together. The doctor plans to open up the space in middle a little. I was wanting mentor memory gel but the doctor said boost is a better implant and safer. I’m very afraid of getting the fake look and want to stay as natural as possible. I’m also going to size 320/340. I’m currently 260/290.