What is the softest feeling silicone implant?

Good questions. Generally, the silicone gel filled implants (as opposed  to the more firm gummy bear implants)  or the softest breast implants available.  Having utilized all three FDA approved manufacturer's implants, I think that they are all quite comparable.  Generally speaking, much of the final look and feel achieved after breast augmentation surgery depends on several factors:

1. The initial shape, size (volume of breast tissue), symmetry of the patient's breasts. In general, the better the preoperative breast appearance the more likely the breast augmentation “look” will be optimal.

2. The experience/skill level of the surgeon is important in determining the final outcome. For example, the accurate and gentle dissection of the breast implant pockets are critical in producing long-term well-placed breast implants. Careful measurements (dimensional planning) and careful selection of breast implant size/profile are part of the surgeon's responsibilities.
I personally think that these 2 factors are more important than any others, including type (saline or silicone) or model (low/moderate/high profile) of implant.

3. The type of implant used may determine the final outcome, especially if the patient does not have significant covering breast or adipose tissue. For example, some surgeons feel that silicone implants have a more natural look and feel than saline implants because silicone gel has a texture that is similar to breast tissue. In other words, if a patient has very low body fat and/or very little breast tissue, the silicone gel implants may provide a more "natural" result.

4. The size and model of breast implant used may make a significant difference in the final outcome. Therefore, it is very important to communicate your size goals with your surgeon. In my practice, the use of photographs of “goal” pictures (and breasts that are too big or too small) is very helpful. I have found that the use of words such as “natural” or “C or D cup” etc.
Also, as you know, cup size varies depending on who makes the bra; therefore, discussing desired cup size may also be inaccurate.
I hope this, and the attached link/video (dedicated to breast augmentation concerns), helps. Best wishes.

Thank you for your question.  The cohesive gel implants are the softest on the market as the gel is not as highly cross linked as the gummy bear implants.  I would recommend feeling each type in your plastic surgeon's office and choosing the one you like the best.  

In my opinion a standard cohesive gel implant will be the softest. The silicone in the  'gummy bear' implants is more cross linked and they are a bit more firm feeling.