My initial recommendation is, if you are not having any issues with your implants, leave them be. This is as individualized as the original decision to have breast augmentation. If you have issues that cause concern, I recommend consulting with a board-certified plastic surgeon. According to the American Society for Aesthetic Plastic Surgery (ASAPS), there are about 300,000 breast augmentations annually. Fewer than 15% of this amount have implant removal surgery, so these numbers strongly indicate that the majority of women having breast augmentation are happy with their results.
Before you hastily decide, you should consider the pros and cons. Besides the cost of having implants removed, probably the main reason not to remove implants relates to your personal confidence, which likely was one of the reasons you initially had breast augmentation. Removing the implants that gave your chest perkiness and a full look will not only return you to your original shape, but your breasts will likely sag more than they did before, along with significant loose skin. Loose skin and low nipple position after implant removal may lead to you not being satisfied without undergoing a breast lift.
Also, while we minimize as much scarring as possible, there will always be some at the incision site and with any major surgery, there are risks associated with anesthesia and possibility of infection.
On the other hand, if you are experiencing breast capsule pain, or if you have noticed a breast shape change that seriously affects your appearance, you should see your plastic surgeon to discuss all possible remedies, and review the reasons for whatever you are experiencing.