I have only two.
For some reason, these and the Firespeeder pilot don't seem to me as "army-build-able" as other trooper type figures, so I think I might
go as far as three of each, but that's it.
Which reminds me, Have you noticed if your DS Gunners have no eyebrows painted on?. I think it might be a production line error, but mine are eyebrow-less.
Perhaps they are Scorch clones?