Over 4000 hrs in the Mexican Flying Cigar!
All what has been written I would say is true about the MIII. The 23 is much better. Both are VERY runway hungry and as mentioned above, is quite performance limited at high density altitudes of say 4000 ft. You're not necessarilly landing weight limited but W.A.T. (weight, airport/altitude, temperature) limited for your 2 segment missed approach climb with OEI, as the limitation needs to be calculated. A Dash 8 300 outperforms the Metro for landing distance reuquired and look at the size of it in comparison. Actually, so does the BAE 146! Be prepared to invest in a lot of water methenol if considering operating at high density altitudes in the Metro.
The 1900 is the other viable option BUT look at the running costs first!!!! I was with 2 x operators who considered the fleet shift but the runninig costs still favoured the Metro.
The Gerretts are noisy as all hell! I used ear plugs as well as my noise cancelling headsets.
The only real other option may be the Jetstream J-32 with that damn spar right in the middle though...
To be honest, I enjoyed the Metro. It is very unforgiving and would kick you in the butt if you got lazy with flying or planning. You DON'T want to get behind the drag curve on approach!!! You'll need a hell of a lot of torque to recover. Do that and then imagine the same scenario at MLW with OEI, hence the limitation as mentioned above.
I hope it all works out for you..... After a year you'll have forearms like Popeye. She's a heavy girl for a slim figure!!!