>>8424626depends on your budget anon.
there is of course the Yamato 1/60 VF-1D (ver.2), which is the best and biggest. perfect transformation (no partsforming), solid joints, holds together nicely. refer to
>>8417747 for size, compared to a 15" screen laptop. but those are rare in the aftermarket nowadays, and go for up to $300.
then there's the Bandai Hi-Metal R, which isn't as big (1/90ish or 1/100 depending on who you're talking to) and has near-perfect transformation (i.e the landing gears are separate pieces, the gun handle is a separate piece, and there's some extra gimmick pieces for the wings on battroid mode), but with the amount of accessories and extra parts it has, goes for $70-100 depending on where you look.
these 2 are your best bet, the rest are either model kits or obsolete/subpar toys.