Denso isn't bad, but around here is seems to be a little more spendy than I'd care to lay out - and I don't see why (I can be convinced to spend extra on parts with good reason - the trick is convincing me that there is a good reason.)
I like Bosch, and probably half of my replacement electrics and sensors are Bosch. No trouble here. I don't spend a lot of time at JF, so I can't evaluate the quality of the tech advice given there. Then again, I take pretty much everything with a significant grain of salt - comes of being a cynic.
ACDelco, Borg-Warner, and Niehoff have all been good parts for me as well, and usually easier to find than most other makes.
Given the circumstances that have eventually led to the production of the XJ et. al. by DaimlerChrysler, I don't think I'd even be mildly surprised to find that most of the OEMR parts now in issue have Bosch stamps on them.
For sensors, you'll find it's worthwhile to not go with "bargain basement" prices - get in the habit of spending a little more for a known good brand. I can't justify the spending of money on parts that are probably crap, and I never have. I see no reason to start now, and I see no reason why anyone else should. That doesn't mean that I'm going to buy the most expensive parts out there, but I've been through more than a few brands, and I've gotten some pretty good ideas about what works without putting you in the poorhouse or sending you to Georgia (in Colonial times, Georgia was a debtor's prison for England...)
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