Sorry to hear that! I know that can be frustrating. Especially with something like a clutch & flywheel where you probably have a certain amount of time allocated for the install, and a shipping delay can push that by quite awhile.
That said: I've bought a lot of parts from Dave @ PWerks over the last four years, and only had one issue - two wires were swapped from their proper position in a MAP sensor harness adapter. (This item was drop-shipped from the manufacturer; the error was there's, not Werks'.) Dave identified the issue very quickly and offered to replace the errant part Real Fast. Fortunately, I was able to fix it myself in about 10 minutes once we identified the problem.
In my experience, stuff like this happens with smaller shops and low-volume cars a lot more than it would with, say, a Miata parts vendor. But, I've found DDM, PWerks and RPM to be very responsive when there is an issue.
Blue-ish 2006 2.4, Werks stage 1 turbo, Borla cat-back, DDM braces, Spec aluminum flywheel, Spec stage 2 clutch, Werks aluminum radiator, some gauges, RKSport hood, Morimoto FX-Rs, GReddy Profec, Norm's fenders
'07 GXP, RPM Stage 2, Solocatless downpipe, TCE Wilwood 6 piston front brakes, 4-piston rears , Stainless brake lines, slotted/drilled rotors, BC Racing BR coilovers, Performance Autowerks intercooler, DDMWorks CAI, charge pipes and braces