Its important to remember that sleeving is performed when the guns original barrels are no longer safe to shoot. Therefore, the value of the gun before it is sleeved is next to nothing. Its a wall hanger. The owner of such a gun has three choices: put it over the fireplace, rebarrel the gun or sleeve the gun. If its a nice gun in otherwise good shape, it is a shame to make it and wall hanger. However, the cost of rebarreling, unless it is a Purdey, Boss or Holland, would far exceed the guns value. Sleeving, however, can now be done well and economically. No doubt, there are poor sleeving jobs out there. Some are sadly comical. But if done well, sleeved guns look very nice, give the gun new life and bring the guns value from zero, with bad barrels, to something much greater. Overall, it can be a very good option. There are quite a few English guns that have been sleeved in England, on the market in the US. The generally represent a very good value for the American hunter and shooter.