The Pep Boys tips work fine. I've used them on the 603 and 103. I can't see spending more for dedicated sockets.

You might dip the tip of a rag in the bolt heads to soak up the oil otherwise the double hex tool might not sit properly in the bolt head. If the expensive tools have a hollow bit then that'll save a step. Still not worth more money to me.

Sixto
95 S420
91 300SE
87 300SDL
83 300SD