I think the G90 comes with 7 topkits,
More match or More Power.
Depending on which you have ordered, I woul do say 4 - 6 in two top kits, 6- 8 in another two kits, 8 -10 in the other two and a 14 in the last one,
The kits will have interlastic side pullers and also be ready bushed.
I would ask the shop to elasticate it for you also what would they reccomend.
I cant comment on hybrid elastic because I never use it, All my elastics are either Preston Hollow, Slip solid , or a micro bore elastic from a company I cant remember.