Let me start by saying these sanding blocks are like that one friend who's amazing at parties but terrible at keeping plans. The Dura-Gold Pro Series comes in three handy sizes (5", 7-3/4", and 10"), and that dual hook & loop/PSA system? Absolute game-changer when switching between drywall sanding and auto body work.
The soft polyurethane foam feels like shaking hands with a cloud - no more hand fatigue after hours of smoothing body filler on my project car. That contour-following flexibility is perfect for curved panels, though I completely understand why some reviewers rage about the slight curvature when chasing perfect flat surfaces.
Here's the real MVP: that PSA conversion pad. Used it exclusively while refinishing my deck and never once had adhesive failure, even during wet sanding. Though pro tip from painful experience - peel off used paper immediately to avoid glue buildup that makes Satan look friendly.
Now the elephant in the workshop: yes, these have more flex than a yoga instructor. When I needed dead-flat surfaces for furniture projects, I reached for traditional blocks. But for automotive curves? These became extensions of my hands, letting me feel every imperfection through the foam.
The hook & loop holds up shockingly well - mine survived six months of shop abuse before showing wear. Just don't expect industrial-grade rigidity; these are the reliable workhorses of contour sanding, not the precision instruments for flat perfection.