WO binoviewer measurements

[neural]

I recently acquired a William Optics binoviewer to use with my SkyWatcher ED100 f/9 and was unpleasantly surprised by focusing problems. Given the recent thread in the Eyepieces forum about this pairing I thought the following might be interesting to prospective buyers...

1. Attaching the BV directly to the focuser without a diagonal (using the 1.25-inch adaptor from my WO 2-inch diagonal) and using the supplied 20mm eyepieces: 34mm spare in-focus, magnification approx 45x as expected. 

2. Attaching the BV directly to the focuser, using the nosepiece supplied with the BV: 92mm spare in-focus, mag approx 76x (1.7x expected). 

3. Attaching the BV directly to the focuser, using the end of a Celestron Omni 1.25-inch 2x barlow (not the whole thing, just the screwed-off end, which looks a lot like the supplied BV nosepiece): 122mm spare in-focus. 

4. BV -> little end of barlow as before -> WO 2-inch dielectric diagonal -> focuser: 18mm spare in-focus, mag approx 145x (3.2x expected). This gives a light path length for the diagonal of 104mm. 

5. BV -> whole Celestron Omni barlow -> diagonal -> focuser: 20mm spare in-focus, mag approx 180x (4.0x expected). 

I wonder if others have made similar measurements for their BVs and scopes, and if so whether we could collate them in a thread or a spreadsheet? That would have been very useful to me before buying. 

Clear skies!