I have both.
I have tried both with basses and skinny stringers and I've never been that impressed with the results of using the G1on for bass or the B1on for guitar.
I think the drives/distortions on both units are a bit weak which isn't an issue on bass because I nearly always play clean but for guitar it's more of a problem.
For me, personally, whilst still being a perfectly usable and decent unit I don't think G1on is as good for guitar as the B1on is for bass.
Since getting a Stomp I don't think I've touched the G1on whereas there are a couple of things on the B1on, such as envelope filters, which I reckon are actually better for bass than the equivalent effects on the Helix.