Bent shields are the fucking worst, it's a pretty flawed design for our use (for machine use, it's fine).
Cleaning them requires the shields to be removed, something that can't be done perfectly every time and results in them bending anyway; in the grand scheme of things it's probably better to pop them when they seize and replace as needed.
Bearings are probably the worst scam in the skate game. ABEC (doesn't apply) Skate Rated (bullshit). The exception to this are BONES Swiss and Swiss Six, they really are head and shoulders above the rest (Shields on or off).