I fell for that trap a few months ago. Replaced both half-axles on my 84 300D with GSP axles from Advance. One failed before the car came off of the jack stands (the clip on the outer joint was left off when they assembled it, so the joint fell apart as I was installing the axle). The outer boot on the other one started leaking grease within 10 miles. Both are being replaced with rebuilt OEM axles once I find the time/money.

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84 300D 255K "Mr B" ("Mr Becker")
79 300D 265K "Mrs B"
85 300TD 175K "Mali" (Sold)
74 Ford F-100 74K "Bonnie" (Sold)
67 Jeepster Commando (Sold)