Using the FNPT2 sim allows you to fly real single IFR. Multi IFR is restored on completion of MEP. I would only renew MEP if I was actually flying twins. If you are on the job market then you only need a current IR to commence a type rating.
That's a little misleading. In order to commence a multi-pilot type rating course you must have a current
multi-engine instrument rating.
JAR-FCL 1.250
(a) Pre-requisite conditions for training: An applicant for the first type rating for a multi- pilot aeroplane type shall:
(1) have at least 100 hours as pilot-in-command of aeroplanes; (2) have a valid multi-engine instrument rating (A);