I bought both of them, since they are at a bargain price and the decals are truly extraordinary.
The Camel is the old Hobbycraft one, and so it is not up to today's standards, but I considered that an aftermarket decal sheet would haven't been cheaper.
They somehow REWORKED the Ni 17, at least comparing the mold with some older HC and a Mania boxings that I have here at hand, but without changing the shape or on the details, they just added some sprue around the wings and a plastic ring around the engine collectors (that helps in avoiding accidental damage to the thin tubes when the model is stored)
The quality of the plastic of these Italeri models seems a little better better than HC's one, a little softer and less brittler, but I have still to start working on them so I cannot be 100% sure - it is an eyesight appearance, not more.