I have to take exception to saying that some planes cannot be brought to better than 0.1 IPS RMS using a DynaVibe. I used to use an ACES system for balancing, but was gifted a low-end DynaVibe unit.
The basic differences between the cheaper and more expensive DynaVibe units, or the ACES unit, are the balancing software and the convenient memory. Fortunately (?) I am a mechanical engineer, so I wrote my own software in Excel to support the balancing process using the cheaper unit.
Anyway, I guarantee
a final value of 0.07 IPS or better, but for most RV's I can get into the 0.03 range! Heck, I've even gotten CJ-6s down to that!
And - (Blatant Commercialism Warning
) - I offer a discount to EAA members that can come to KFFZ for the balance.