If it`s a 686e you want then go for it, second hand or new they are a very good bit of kit for a first clay gun.
Providing it fits well then your away, it will last you years even a second hand one because they havn`t been out long.
However as a coach I would say that the first thing to do is get a couple of lessons and let the coach sort you out, it`s something that you will not regret. A good coach will tell you if the gun is right for you or not and show you how to use it well and of course safely.
If possible buy a gun from a shop that has a shooting ground on site, that way you will be able to try before you buy and maybe get a quick free short lesson.
Good luck.