Kent is full of it, he seems to thrive on spreading FUD. It's just a metal bellows housed in an aluminum case with 2 rubber O-ring seals in it. Having done several, I can assure you they are not "done" once opened. If the seals leak, you have to build that much more boost to overcome the leakage before the bellows collapse and lift the fuel enrichment plunger on the IP.

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Current stable:
1995 E320 149K (Nancy)
1983 500SL 120K (SLoL)

Black Sheep:
1985 524TD 167K (TotalDumpster™)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)