As discussed in the other thread, OWO is low risk, and its up us punters to weigh up the risk/reward.
Same applies for RO.
For my first few months of this hobby, I would do both whenever possible.
My current take on this is that I only give RO to a WG if she is especially attractive. In which case, I'd like her to return the favour with OWO.
No STDs yet.