I seldom take my .243 out, unless targeting deer only. I have £2800 .243 set up, but prefer to take out my Hornet that cost me £400 second hand. I only wish I had one earlier in my shooting life.
If you are really honest, there are not many foxes shot over the 200 yard range.... And therefore I fully recommend it as you first centre fire rifle.
They are becoming harder to locate second hand as they increase in popularity, a kind of 'Retro' comeback
If you are close to Dundee, you are welcome to try all of the calibres listed above, and .223, 308 etc and make your own mind up!