I'll talk about the ferrari P4 as i ever had the opportunity of owning both the fujimi & union before.
the fujimi kit has better body construction & well defined panel lines, better decals, p/e fret & pre-painted wheels.
the union kit scores with a full engine, & full working suspension. but i must stress that the union kit maybe some 10years older the the fujimi kit.
i sold off the fujimi kit as i'm very particular about models not having a engine or a decent suspension setup, so unless you are a detail-minded builder like me, i suggest you go for the fujimi 'quick' build...
hope this helps
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I can feel the adredalin,
the same adredalin of what it's like...
to be a classic ferrari coachbuilder.