The Dorman boots I tried are a multi-size design - made to be cut to fit. The portion suitable for the Mercedes axle was similar to OE except for maybe having an extra pleat. If I could've easily separated the joints, I would have used the Dorman boots, but they just wouldn't stretch enough using the tranny-funnel, and nobody around here had the special tools.
Compared to the Dorman boots, I've read posts here that the Astoria boots are thinner/softer/looser, but some have had problems with them getting pinched/cut in the joints during axle installation.
Others have had the boots split when they tried to stretch them. Fortunately, I was able to return my Dorman boots before I wound up ruining them.
My local MB parts-place has the CVJ axles in stock, so I'll probably be going with those.

Happy Motoring, Mark

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DrDKW