Although my Nova Reverb is superb in the ODS loop I picked up this excellent, no hasle, Holy Grail nano, so thought I would test it in the loop.
While I had my test gear & scope set up I also tested a few other pedals:-

Here are all the readings :-

Pedal                 Max before clip   Watts       
-----------------------------------------------------
None                          14.2V             50                 
Holy Grail                   10.6V             28 
Mad Prof Del                7.3V             13                       
Nova Rev                    14.2V            50                             
Nova Del                     14.2V            50

Measured across a 4 Ohm dummy load.
An interesting finding was that contrary to popular belief my ODS pumps out 50 Watts of clean signal before it clips     Not 43 as I have often read 

So the Holy Grail Nano will start to compromise the clean signal at 30 Watts.
Mad Professor delay clips at only 13 Watts.
Both Nova Reverb and Delay are transparent in the loop. ( provided they have been calibrated ).

Could use the nano in-line but don't like the wash of reverb when the o/d is engaged.
Back to the Nova then. Wish it had less knobs 

I'll use the HG for my Dizzy 30 and Egnater. It's an excellent simulation of an old spring reverb.


John