In terms of value for money, you'll probably be able to get more MG for your money - but if it's pure driving thrills your after with one eye on track days, then the MX-5 is the car for you. Both cars have strong club support and plentiful parts supply. Have you considered an MGF? Where the TF uses a conventional spring set up, the F uses hydragas. Try as many as you can to see which you prefer - and make sure you do your homework. You should be able to find an MG with a loving owner and full service history that has made the necessary upgrades to the head gasket within your budget. Winter is often considered a good time to buy but don't forget fewer cars will be for sale at this time of year.