What Jon said. Looking at injecton-moulded Spitfires from mainstream manufacturers, such as you might find in your LHS, the Airfix 1/72 Spitfire Ia and Vb (not the Vc) are /more accurate, and much cheaper, than the Tamiya kits, but not as well detailed, and have raised panel lines and much worse decals. By the time you’ve factored in the cost of replacement decals, in fact, the price advantage is mostly eroded, especailly as Airfix have just put their prices up by about 10%.
The Tamiya I/Ia and Vb kits have some accuracy issues, mostly around the wing planform, but otherwise they’re very good kits. I suspect that you’d only notice the accuracy issues if you knew exactly what you were looking for (I do, so I do. Do you:


?)
The Hasegawa VIII and XI are nice, accurately-detailed kits, but not especially cheap, and the Heller XVI is surprisingly adequate. Italeri do a Vb and a IX, but there are serious fit and accuracy issues around the nose. They’re cheap, though, and I’ve heard of people using them as sources of detail parts and decals for the Airfix Vb. Hasegawa do an early Mk.I, which, while cheap, is also a bit crude. It does come with a twin-bladed prop, which is good to use on the Tamiya Spit I/Ia for a very early bird.
The Revell Germany and Hobbyboss Vbs are crude, inaccurate, and worth avoiding.
The Fujimi XIV is nice. The Academy XIV isn’t. Nor is any XIV emanating from Eastern Europe or Russia.
The Airfix IX, dating from 1958, is worth not just avoiding, but running away from. Fast, very fast. It remains to be seen how much of an improvement the proposed new Airfix kit is, or, indeed, whether, with so many Daleks and Shaun the Sheeps taking priority, we’ll ever actually see it at all.
To conclude - If I were just starting in the hobby, with maybe half-a-dozen kits under my belt,and looking for a 1/72 Spitfire, I’d go for either the Tamiya 1/72 Spit Vb, because of its good detail, adequate level of accuracy, interesting colour schemes and good decals, or the Hasegawa VIII or IX, because of its overall niceness. If I wanted a simple, inexpensive build, I’d go for the Airfix I/Ia.
Cheers,
Chris.