The OR5 is getting very high praise from some folks I typically trust for non-BS impressions, so I'm really curious about it. Basically they felt it made a very big difference in what they were hearing over other stuff they've tried before like the Audiophilio. They went into it with a highly skeptical attitude not expecting much in the way of gains.
Apparently Empirical has a money back guarantee, so that's enticing too. Even if they're attributing the improvements to unicorn horn powder and mermaid scales, I'd be down for one if I could hear definite improvements.
Money back guarantee is pretty nice, I'm pretty set on trying an offramp one day, I might need to try to organise a comparison with someone locally who has one, but they are fairly rare. Same goes for Berkeley Alpha USB, pretty hard to come by. I have only seen one negative impression of the OffRamp against many positive, as well as questionable measurements in terms of jitter performance, but as you say money back guarantee negates the risk, and measurements are not the whole picture even when it comes to digital transports. Next upgrade for me will probably be the Berkeley Alpha USB, probably in a month or so. OffRamp maybe after that, once the updates for the OffRamp are implemented.