But i think that companies prefer an ir on a bigger aircraft
Wanna-Be. An IR is an IR it makes no difference whatsoever what size the aircraft is. All aircraft used for IR training must have minimum instrumentation for the training anyway.
The TC for the Schweizer 330 (269D) states "No instrument flight" so Heli Holland must be using a Bell 206 or some other instrument certified helicopter for the final 10 hrs of training on their IR program!