IIRC, I thought 33cm was the length given for the figher mode of the 1/60 VF-0S, not the height of the battroid mode. Anyway, whether it's fighter or battroid, 33cm is still bigger than the 1/48 VF-1.
I'm not at home now so can't measure my Hasegawa kits, but the Macross Compendium gives the full size measurements of the VF-0 and SV-51 as follows (VF-1 length thrown in for comparison).
VF-0 length in fighter mode = 18.69 m
SV-51 length in fighter mode = 22.77 m
VF-1 length in fighter mode = 14.23 m,
So we can see that the SV-51 is slightly more than 4 meters longer than the VF-0 and a whopping 8.5 meters longer than the VF-1.
Graham