I've never had a problem with generic CV boots. In fact, VW boots aren't known for having very long lives anyways.
However, VW axles and joints are pretty good and generic ones tend to be not as good. Sometimes they work and sometimes they don't. I would stick with a genuine joint. The left and right inner CV joints have different part numbers but I don't know what the difference is. The inner boots also have different part numbers. The tripod/triple roller style appears to have the same number. The outer joints have the same part number for left vs. right.
FYI here is ecs tuning's page with part numbers: http://www.ecstuning.com/Volkswagen-Jetta_IV--TDI/Drivetrain/Driveshaft/
However, VW axles and joints are pretty good and generic ones tend to be not as good. Sometimes they work and sometimes they don't. I would stick with a genuine joint. The left and right inner CV joints have different part numbers but I don't know what the difference is. The inner boots also have different part numbers. The tripod/triple roller style appears to have the same number. The outer joints have the same part number for left vs. right.
FYI here is ecs tuning's page with part numbers: http://www.ecstuning.com/Volkswagen-Jetta_IV--TDI/Drivetrain/Driveshaft/