I own a small 40 room Motel and currently have installed a Mitel 200 analog system (217). Amazingly after 20-plus years the sytems is still working fine but I want to plan for the day when the system does eventually go down.

I was looking at acquiring a SX-50 or possibly a 200sx el\ml and keep the old sx as a backup but I have a few questions before I make my final decision.

As far as connecting either a SX-50 or SX-200 el\ml to the current wiring configuration how extensive, if any, would the wiring changes be?

Could someone explain to me the differences between Mitel's EL and ML version.

Final question has to do with MOSS Sheets and if I bought a Mitel EL\ML with a moss sheet and added hardware would I need to get a new MOSS sheet and if thats the case how does one go about that.

I'm leaning towards purchasing an SX-50 because at this point I think it would be simpler to implement but I'm open to any suggestions.

Thanks in advance to any and all input.