Not convinced its one panel on the 3200, but filled and finished smooth...I think the eurospares shows the wing as separate. Many panels look like one piece but are in fact welded and finished smooth.
Both are very pretty. But the more svelte lines of the 3200 and it's higher build cost/effort/detail (not to mention the boomerangs) swing it for me. I'm convinced it's the "investment" car of the two, and certainly I'll be looking to buy a good one soon (while they are still available) to tuck away for a while.
3200 was lead loaded which is why there is no seam.
I could pretend I was a closet anorak but thanks for this nugget of information goes to Mike at The Maserati Shed who passed this onto me when we were discussing merits of various models the other day. I am however of an age where I know what lead loading is and have tried it out on a Mk2 Jag a number of years ago. The people who do this (well) are very skilled. Can see why Maserati decided to discontinue the practice.