Yeah I know I bought another marker this summer but hey, I needed a backup marker.
Both marker compared :
Markers size compared :
Stock barrels compared :
Vs2 barrel w/blue barrel tip VS VS1 stock barrel :
Both bolt compared:
Look and size
As you can see, the VS1 and the VS2 are like brothers. Both got the same size. Both can use same barrels, and both have identical bolt. However, the position of the hose on the VS1 makes it a little harder to hold the frontgrip (i like to hold it with my whole hand). So it feel a bit like a mini, you have to let the left hand open to shoot it, not a big deal, but I don't like this feeling. I'll surely get used with time.
Also the VS1 is definately lighter than the VS2. In a previous thread I wrote that the VS2 was pretty light compare to my old TL-X, and the VS1 is much lighter (girlfriend verified

)
Firing mode
The VS1 have the exact same firing mode as the VS2. Semi (capped at 20 bps, the vs2 is capped at 25bps) and 3 burst shot. However, the VS1 can use eyes with the 3 burst shot mode, where the VS2 can't. Also the VS1 can indicate if there's a problem with eyes. In that case, the upper LED start to blink. If that happen, eyes are still working, but the board lower the BPS cap, so you won't be able to shot at the same speed.
I did not had time to test it yet, I came back in town and it was raining so much, so I'll write the rest tomorrow.