Upgrading 5* cards

Mishumo wrote:

Is it advisable to upgrade 1 or 2 5* character cards with iso - or should I leave them until I have collected quiet a few cards?

I am not upgrading them until I have 6 or 7 covers, they are not very good until that point, and I don't want to mess with my scaling.

Edit: Maybe the only 5 that is worth upgrading before is Phoenix, IF you have at least one green cover (because Phoenix Force doesnt upgrade with covers just with levels and from the start is quite good - 4k damage AoE for 9 AP is very good). I guess I will start putting iso into her earlier than the other two.

If you have quite a few 4*'s maxed out, then taking a 5* to 350 should not touch your scaling, as that is where a boosted 4* lands when max.