Newbie question about RTEMS API

[Aaron]

Hi all,

I'm just getting started with RTEMS. After a couple head-scratching moments, I've got some simple hello world style programs up and running. I'm ready to get down to business, but I've got a quick question for you all.

RTEMS has three APIs basically, the classic API, POSIX API and uITRON. I'm wondering which I should use. Here is the problem.... I don't have any legacy code or any code that will be ported over to my application. I'm using RTEMS to power a hobby robot. All I am interested in is ease of programming and the most speed I can drag out of it. I'm not overly familiar with any of the three APIs, so I don't have a preference.

Are there any disadvantages to using any one particular API over the other? For instance, will using POSIX slow my system down a bit? Will using uITRON mean that I'll have to fight with the API changing from release to release? 

I guess I'm just looking for advantages/disadvantages of each when no legacy code is being thrown into the mix.

Thanks!
Aaron