I'm using a 1x9 on my RC303 at the mo and have had no probs yet. I have a roller and a shorter chain. I have also kept a 22T granny on the front for emergencies- if things get too steep for the 36T on the front I just put my toe on the chain and push it off the middle and onto the granny- getting quite good at this with a little practice. Also having that ring there helps if the chain should decide to fall inwards.
Si
Si