To be honest, i think if you have an idea what to expect in the FEAST, SDM and Phase 2 tests, you will have an advantage. By idea i mean knowing that there will be a coordinate test for example, and roughly what youll have to do. I was surprised by the amount of people who had no idea there was going to be a cube test in teh FEAST package. Not surprisingly, they didnt pass.
With SDM, just take your time, i didnt find any opposite conflicts but still got through.
The interview is the bit to worry about, where they will root out a lot of people. Happily they do give feedback, though im yet to manage to get hold of the guy who provides it!