I've been through ~8(?) checkrides. Each was a learning experience but none were "hard". Each was an oportunity to fly with a high time airman and on every one I learned a lot (sometimes not about flying); on my CFI ride in particular the examiner learned a lot as well (I had a more extensive knowledge base that he, in an area he chose to have me discuss).
ON my CFI-MEI ride the examiner definitely AND willfully went for 3 red and one green on the single engine landing AFTER WE HAD DISCUSSED TWO GREEN/TWO RED WHILE ON ONE BLOWER. He had the aircraft "taken away from him" for that, we landed full stop and I had a little talk with him in which pointed out that I would be complaining to the FSDO if he EVER tried anything like that again. The rest of the ride was relaxed.
Principally the thing you have to be comfortable with are "that the outcome of the maneuver shell never be in doubt" meaning you stay in the middle of the "this will work out fine" envelope and not at the edges. And never create a real emergency.