Its a challenge
Hi
I finished my MECIR 3 weeks ago. It is really challenging, and I was working at the same time. I did the sim sessions 3 times a week with the instructor, and then flew twice a week in the later stages. This gave me time to think about what I was doing and to plan for the next flight. Other places suggest doing it fulltime ie in 4 weeks.
Using the Flight Sim on the computer was very very helpful. I would fly the next nav many times before actually flying the real nav, this really helped me.
I was lucky enough to have almost 100 hours twin time before doing the MECIR, this really helped. As others have said you need to know your plane! Particularly flying on one engine.
It also helps to feel very comfortable in CTA, which you should be with a CPL. When flying by hand, trying to keep up a scan, dealing with a simulated engine failure, the pressure mounts.
Good luck
JERR