In terms of what "Symbol" said about which was better to fly or fight in, this is very subjective and relates more to the individual pilot and how they liked to fly. For example Bill Dunn, the first American ace of the war, who flew both the Spit and Mustang in combat always said he'd choose the Spit anytime but obviously another American Goodson, preferred the Mustang.
A matter of horses for courses really.
You can call me 'Broad Arrow'. Or John. Or Fat Boring Old Fa... Oh, look! Something shiny!
Yes, what I posted was the opinion of one pilot who owned both. I've never flown either, so I don't have an opinion. But were I to be walking along the beach and find an old Middle-Eastern lamp that could do with a bit of polishing, I'd take the Spitfire just because it's a prettier machine than the Mustang.