I just got one. It arrived today. I also have an Axe FX III and have run it in 4-cable-method with my Diezel VH4, Marshall JVMJS, Mesa Boogie Dual Rectifier, and Mark V amps.
I am a big fan of the Axe FX III's delays and reverbs. But setting up the Axe III each time for practice and gigs is a pain. Having a pedalboard that I can just plug a few cables into and get going is just way more fluid and intuitive to me.
4 effects may be limiting, may not be. It depends what you want to achieve.
There are plenty of footswitch combinations you can use to access different presets, scenes, and effects block channels - you can have access to 4 reverbs all within one preset simply by using the ABCD channels on a reverb block. You've effectively got access to 16 channels across 4 effects. So plenty to be getting on with - provided you don't want to use them ALL in one song, coz that might be a pain.
You can setup an input noise gate without using a block. You can also setup an expression pedal to control either input or output volume, without taking up a block. Of course you can add other pedals to the setup too. Most people seem to add their own favourite drive pedals, and use the VP4 for modulation and delay and reverb effects.