W202 tracking. Wheels in motion, or just use an indie

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My C230 has pulled to the left a little ever since I bought it a year or so ago. It's due new tyres all round so figure I might as well get the tracking sorted on it too. I've heard stories that some Mercs can be tricky to sort out and I'd be best taking it to a specialist like WIM.

I know WIM do a darned fine job, but will my local Merc specialist be able to do just as good a job.

Experiences?