It really depends on your target audience, I've found. At previous companies, IP inferred data was always iffy on company name - I experienced the same thing you did. But that was because we were selling to small, local businesses unlikely to have anything other than their ISP listed. In those cases, I most certainly wouldn't think RTP would be a great fit.
Currently we target larger organizations, many of which are public, and generally have decent results from inferred information. We haven't sprung for RTP yet, but I could see a better fit in my current use case.