get the JPemu as most of the half decent files are in this format. as for getting the latest machines, i believe a machine has to be 3yrs old before it can be legally emulated...so that kind of answers your question
Anything above MFME 9.4 will sort you out with MPU5s/S4's, the 3 year rule doesn't seem to be taken into account that much, it's certainly nothing to do with illegality, there's a Corrie emu being made just now, less than 2 years. A whole load of newish Crests/BFM's and Mazoomas out there to be played.
thanks for the advice.however where can i get the mfme 9.4 or above.looked on fruit emu not there.googled and not there even found a link on here but the web page isnt there.