Depends on your goals, tires being used, etc. for the front. If tracking typically as high as you can get. Rear most seem to aim for between -2 to -2.5 with toe in.
I believe it does help. Don't quite me on it though. Most people I've seen with verus camber plates whether stock struts or aftermarket are able to easily achieve camber in the 3s
I'm also stock shocks with H&R springs and verus camber plates. Currently -3.4 up front on 18x10 275 with 13mm spacer. No issues at 10k miles and 16 track days.