It's not like I have anything against earlier Marks. .... there are just parts I like better.  Especially those with more performance...  

The Mark V came out in several guises but the one I enjoyed most was the model fitted with the Merlin 50M engine, and the 'A' type wing. This was a de-rated engine, designed to give its maximum power at 5500 feet. It had of course a big advantage at low level and with the enormous increase in boost pressure, was a joy to fly. In fact it was the only Spitfire during a demonstration that I felt able to take-off, lift the wheels up, pause & then pull up firmly but smoothly into a vertical loop with a slow-roll off the top to finish over the centre of the airfield. If I had to make a choice of all the numerous marks of Spitfires - and there were over thirty-six of them -  this is the one I would have picked for a low-level display.

I note from my log-book that I flew the first Mark IX produced at the Castle Bromwich works during March 1943. I think it would be fair to say that this was the period when the poetry of R. J. Mitchell's genius began to fade - but only in looks. This was due, not so much to the design alterations in the Spitfire but rather to the remarkable improvement in the output of the new Merlin.
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The new engine necessitated fitting a new cooling radiator under the wing and also extending the nose by nine inches. I also seem to recollect that longitudinal stability problems were creeping in and that the tail was modified. However, in spite of this, it still looked very much like the original masterpiece. Its performance as a weapon of war was better but, sad to say, I felt the superb classic flying qualities of the old Mark II were slowly being eroded.

It's not like I have anything against earlier Marks.  It's like asking which part of Charlize Theron I would rather see naked!  Any part will do, there are just parts I like better.  Especially those with more performance...  

With that in mind...