Our Sim is ZFT rated, and it is fine for initial training. The fact that it is harder to fly than the a/c is no bad thing. New pilots can make errors without endangering themselves and others.
A sim cannot, however, simulate Operational C2 R/T and pressures, or an NVG strip landing in high terrain, but as a procedural trainer, they are great value for money.
As long as actual flight is also part of conversion training, I don't see it as a problem.