hey.
recently, i installed two of these on my commuters.
shimano Deore M617.. found them at merlin cycles for 50 or so bucks
one i managed to install on old mountain Mongoose that i converted to cyclocross commuter, that got stollen i ran both as single setups.
anyway, they work great, im 230lbs and they support me nicely.
on both i just took off smaller chainring. you can install one-by or like me just use pre-installed chainring and deal with occasional chain drop.

best,
z