I did mine in a Baron and imho if you do it in a twin with performance like that you also have to learn to observe your speed limitations etc. Which in a P68 or Seneca etc you will have trouble breaking even if your not paying attention.
The HSI/RMIs etc are all very handy but if you go learning with them and end up flying an aircraft with just the bare minimum equipment then you may be at a disadvantage, and in bad weather conditions down to the minimas that may be the difference between a safe approach and arrival and a missed approach or worse.
But of course any good school doing MECIR training should cover all this and make sure that no matter what equipment you have or aircraft that you are flying, that you are capable of conducting approaches and ops under the IFR safely.
My 2cents
