There's not a lot of practical difference between a convection oven (such as is installed in an RV) and a toaster oven. The convection oven, in convection mode, is basically just a toaster oven with a fan to move the air around inside. Many toaster ovens have a convection or turbo mode where they also have a fan to move the air around inside. I would be slightly surprised if there was much difference in warm-up time for similar sized units.
That said, in my house, I'm rather fond of my toaster oven for smaller cooking jobs, particularly those that don't need super precise or even cooking. It does the job decently.
