The difference between natural breasts and those who had implants put in is fairly simple, anyone with implants has a VERY unnatural lift to their breasts , basically they defy gravity as the the implant has very little give especially if on top of the muscle, so for example a woman with natural say H size boobs , will have a round look but tend to have that natural slope or droop from the weight of the mass, a woman the same size when her top is off her boobs will stand out as if levitating , the other factor is the firmness, natural will have a slight resistance when firm ,but will give under the right amount of pressure, while implants barely if at all (again depends on how put in) will feel like a basket ball that needs air, another is the scar tissue build up from the surgery, it doesn't matter if the surgeon goes via arm pit, under the breasts, the aureola , the inside tissue is cut, manipulated and pushed about to seat the implant , this trauma causes scar tissue, if not felt with scar tissue can become like cement , hence another reason the boobs stand out stiff and no sway, so to press and push nature boobs to fake boobs, is like natural against a wall, you will get some shifting of the flesh but over all it is a losing battle, the last really big thing is the level of sensitivity , naturally when a surgeon makes his cuts your cutting tissue, muscle and nerves , while these nerves can regenerate it takes a long time if they do but also even if they do there is a level of loss of feeling or sensitivity , so basically implants can be pushed,rubbed,pressed so on for hours and the woman with the implants will barely feel it if at all, in some cases, where as natural after about 15 minutes get that deep ache and swelling and thats the point that a breast fight can get intense as you fall back on your ability to to have a high tolerance to aches and pain.
To put it more clearly, you can ask any woman especially your girl friend or wife, or just take notice next time your intimate, after 15 - 20 minutes (depending on the person) it gets annoying for the woman to have her breasts pushed,squeezed,pulled basically worked, then she will pull her chest away,move your hand what have you, (this may not include her nipples worked but the mass over all), we experience swelling, ache feeling and well it can become annoying , so imagine 2 sets of breasts probing, push,pull,drag ,smear collide ,pump ,press mash, so on for anywhere between an hour plus, the muscles,the tendons, the ligaments ,tissue so on in the chest that hold the breasts get worked as much if not more than the actually boobs, I personally have had to use warm then cold compresses on my chest and boobs to not wince in pain after a long match, implants will not suffer as much cause the saline sack surrounded by muscle and scar tissue and the general composition of the implant that holds the saline has little room to budge , so i the chest cavity it is secure, a prime example was the famous Sable , at least two times after doing moves off the ropes and landing on her chest blew her implants and had to get them redone, there is no place for the mass to go so they simply burst, so pushing natural where they can swell, shift,lift so on against a tiny sealed unit that has made a two inch surround of rom has no where to go, think of it like a zip lock baggie filled to the top with an inch to two inch of air room, then squeeze it till all the room is filled , either the natural pair yield or the bag will leak or burst . hope this answers your question