The only way to definitely say you didn't have the Bkool fairy dust help is to try a Neo, Atom, Kickr, powertap or other power meters
The qualified accountant in me insisted I carry out a cost benefit analysis and the findings are the cost of £300+ doesn't give me any real benefits given my objectives of using the turbo. Knowing my real power number, assuming the Pro is over reading, won't actually get me any fitter. I ride for 60-90 mins and I'd still be doing that whether I have a power meter or not.
I've been researching the power meters and as always there are pros and cons of each one; at the £300-£400 price point there is the obvious issue that I can only get a one sided meter which may not be that accurate if I am significantly weaker on my left side and I'm not prepared to shell out double that for a two sided meter.
Maybe if my Pro fails then I'll reconsider options but for now I'll stick with what I have. If Neo users want to beat me, they will need to be x% (add your own number for x) fitter than me
Definitely not interested in the Neo or Kickr as don't like the fact I'd have to faff with the rear wheel and also buy and fit a separate rear cassette. Powertap pedals not an option as they require new shoes. Stages and 4iii I've considered but they get mixed reviews, and if I'm aiming to get better accuracy over the Pro these don't guarantee this. The Atom I'm keen on as it does give benefits over my current set up, namely no dropped chains, no flat tyres, hopefully easier/smoother gear changes but I'd want to see real life reviews before spending that kind of dosh.