Personally I'd go for the Granstar but that's purely down to me lusting after one because of the pastel colours and Art Deco inspired lug when they were released in the mid 80s. 30+ years later and I haven't shaken it off.
Definitely Granstars between those two choices. I've only played probably two of each 3000 and Granstar kits, but the Sonors didn't have the same big meaty low end that the Granstars have, and the Tama lugs look better to me.
i think the 3000s were aimed at the top of the mid level range, whereas granstars were tamas old high end kits alongside the artstars, so i would go with granstar. do you know if theres an 11" tom with the granstar?
I'd keep looking.. those toms are huge on both kits. Unless you prefer lugging giant drums and being hidden behind the kit.. also the stretch from the snare to the high toms is not ergonomic. Power toms had their day.. they can record beautifully.. but there are better more compact options out there that sound awesome.
I think the Sonor has a thinner shell, but not by much (edit: Sonor-9ply/7.5mm toms & 11 ply/8.5mm bass, Tama-7 ply/9mm)
I remember those Granstars were fairly thick, but they sounded great.
The Metalhead's go-to drum back in the 80's.
Sonor 3000 has a lot of fans, and Sonor makes some really great sounding drums.
I became a HUGE fan of Sonorlite's back in the 80's and currently play a set of Force Customs, but I also accented my Ludwig kit with a Stagestar snare drum, so I don't have any particular allegiance's
Wish I had a better response for you, but I really just wanted to post the Granstar catalogue, since Woowich posted the Sonor 3000 catalogue.
Good luck and show us what you ended up with, even if its neither.