If we're talking about early gems, I love using the BMW 507 '57 which even at something like 362PP is more than able for the other cars in the Novice league, even at 500PP. I'm sure tuned up it would give the higher level cars a good run for their money too.
I think it was GT4 I used an MX-5 early on, then went for the ZZII upto the GT500 level - definitely a good car.