If you can't tell the difference then it makes no difference.
The hardness in an enhanced tit is caused by capsular contraction and it rarely happens immediately after surgery, so a girl could go a year or two with a nice, natural feeling pair of bolt-ons only to have them harden up in year 2 or 3 as more and more scar tissue forms and squeezes the implant into an oddly shaped ball protruding unnaturally from her chest. Bummer. Some of the WGs I've seen over a 5 year period have had this happen. I remember one in particular that got her new boobies and I was shocked the first year how natural they were. I thought it was the magic of the surgeon, but she told me she'd actually had them done, at a discount, in the plastic surgery training program for interns/residents in one of the local hospitals in California. I was absolutely amazed they were such nice looking tits.
Well, anyway, flash forward 3 years or so and they are still not ugly, but they're clearly a pair of store-bought titties: hard, round and sitting somewhat unnaturally on her chest.
I've seen estimates floating around the web that the incidence of capsular contraction is somewhere between 10-50%, which is such a wide range as to be ridiculous and says something about the rigorousness (or lack thereof) of plastic surgery as medicine. I think one researcher, also lamenting this uselessly wide range, said that perhaps it could be interpreted as a 50% incidence of level 1 (the least hard) or higher capsular contraction, and 10% of level 4 (the hardest and weirdest looking).
There is a new technique being pioneered in the U.K. where they use stem cells and body fat to inject. Apparently the new cells do take and develop their own blood flow and therefore survive. It's still early in thetrials, but this 'all natural' technique does appear to be good for an additional cup size . . . y'know . . . just in case any of you guys are in the market for some man-boobies.