Did mine on a Seneca 2 in 2009. A few quick thoughts;
-you'll need more capacity, and will work harder due to higher cruise speed, 2 engines to learn etc.
-it's very very expensive if you partial or fail your test and need retraining and retest.
-it will take the pressure off you during your ME/IR, but that's not very important when compared to the two points above.
-it is more fun
Having said all that, given the choice again I still would do it on a multi.