Boss VF-1 Effect Processor

Is anyone familiar with both the VF-1 and GT-6?  I'm thinking about 
buying a VF-1, but since by far my main use of it will be with guitar 
I'm wondering if I would do better with a GT-6 instead since it would 
give me easier access to most controls.

I've played with the VF-1 and like it, but haven't found a GT-6 in 
stock yet.  Does anyone know how the two units compare?  Do they use 
the same basic models and effects?  Is the quality of effects roughly 
the same?  Are the algorithms similar?  Since the GT-6 is newer, does 
it have more or better amp/speaker models?

Also, since the VF-1 has been out for 2 1/2 years, I'm wondering if 
Roland will be coming out with a "VF-2" soon.  How far apart were the 
releases of the SE-50, SE-70, and VF-1?

Thanks.