Oh yes, we've been through our fair share of "plastic" vacuums...a Eureka 6.5-amp Bravo TheBOSS, an Oreck pair...upright and minicanister, one of the early Kenmore Progressive uprights (which wasn't a bad vacuum except for the belt lifter that kept slipping...that was always in the Sears repair shop), Eureka Mighty Mite and EuroPro Shark compact canisters, and a Eureka (built for Wal-Mart) GE bagless upright. The last ones to go were the previous two, and that was last year. Only vintage machines and a wide-track Sanitaire occupy the two hall closets here.
The Convertible really does clean those rugs well (definitely better than the previous machines), and I just replaced the belt, changed the bag, checked the bearings, and gave it a good cleaning last week. I'm the only one who uses the rear-conversion accessories, and I rarely do that; an early-80's Simpson-Sears compact canister (identical to the Kenmore SPV or Super Power Vac) does the above-the-floor cleaning. It is constructed of plastic, but is surprisingly durable and very lightweight to boot...and yes, powerful! Pete, I'll get a picture of that one sometime so you can see what it looks like.
--Austin