I currently use a Garmin Vector S set of pedals for (single sided) power measurements. I'm OK with that, but I would really like to know what my left vs. right balance actually is. I am not particularly motivated to 'fix it'. But if it is 45/55 vs. 55/45, that results in a pretty big difference in actual power vs. 'reported power'.
So all I really need is some kind of two sided measurement capability for just a ride or two and compare the readings. I have considered trolling for an older Powertap hub/wheel in ebay (I run Campy Chorus 11sp, but I understand that Shimano 11s cassettes are close enough that you can make them work in a Campy setup), use it a couple days, and re-sell for a net cost much lower than the Garmin Vector 2 sided upgrade cost.
I know that the G3 is an Ant+ device (handy for me as I use a Garmin 800 Edge), but I understand that the older (and therefore cheaper) PT's are not.
So my question is if I get an older PT Hub/wheel what kind of readout device do I need? It would be really nice to have a .fit file for comparison purposes, if that is possible.
PowerTap hubs used ANT+ prior to the G3. Older PowerTaps were wired (cannot be converted to wireless or ANT+). Later they had wireless versions, but not ANT+. These could be converted to ANT+ with a kit. They later released a ANT+ model -- again, prior to the G3. If you get a pre-G3 model, just ensure it is ANT+. But that aside, you should be able to get a good price on a used G3.