VG30 on a 20 is crap, dont do it. I did the swap on my hr31 and it was really laggy, to the point that normal daily driving was a pain in the ass. I changed back to the stock turbo I hated it so much.
Go a highflow of the stock turbo, much better option, not alot of lag but alot of potential, my 32 had this and it made about 230rwkw and less lag then the vg did (tune would also help with that)
Dont put a op6 rear housed turbo on a 20, worst thing you could do in terms of drivability, would only be good if you used it for a highflow and wanted 250rwkw +.
Really any turbo bigger then stock is gonna suck unless you get a tune.