We ran the 180 series and had zero chunking. But then again, we are not as fast as the Top Turbo guys.....yet!I don't know if I woudl say tons of low 7 passes Ryan. Only a few used them and all that I know of other than the GI joe 1000 have had pretty significant chunking on them with a relatively low number of passes. The longest I know of lasting is one that was on Mark Paquette's bike that Tyler Fisher had on it, and then Bud rode at the October MIR race. I believe it started chinking on teh 15th or 16th pass. Bud still rode it after that.
I did some testing with them and found the 200 seems to hold together a bit better than the 190, but still had chunking. Power 1's will chunk as well, but they usually don't get worse in a rapid manner (other than the large chunk that came off of I believe Shannon Maylee's). I know of Power 1's that had chunks and still made many 6 second passes without any appreciable growth of the chunked area.