OT: setting the gain

[Ben <benoitruelle@yahoo.fr>]

Hello

This is quite OT but I think I may have usefull info from the techwizards 
on 
this list.
I recently bought a zoom G5 pedalboard (a kind of M13 for the poor ;-).
I use it in front of my Fender Mustang I Combo (no FX loop), I wonder how 
I 
should check the gain so the signal/noise ratio is the best without sound 
distorsion. 

The factory presets on the G5 have a lot a volume difference and my 
question is 
how do you assure a correct level when using a multi FX like this and make 
an 
even sound among presets?
Is the best solution to use a VU-metre on a mixing desk to create the 
presets?
I sometime uses the clip led of my jamman but this not precise enough. As 
the 
amp has also its own amp modelling, using the ear is not enough to detect 
if the
distorsion come from the amps sim on the G5, the input overloaded or the 
amp sim
on the amp.

Any input?

Ben