Surprise Update! Yes I am over the top...
Well, I decided that if I was going to really do a serious comparison, there was no way that I could not include rcplanebuyer. I have purchased a number of sets of his 13-bar Genesis flavorizers and at least one set of flavorizers for the sidewinder 300 and also a few of his 300 series heat deflectors for the front control 300 series Genesis. (In fact, I helped Dave with these by sending him an old one to use as a template.) However, I have never owned my own set of his grates that I have seen you all extol here on TVWBB.
My BBQParts.com set arrived this morning and rcplanebuyer ones arrived this afternoon. I am not wanting to start my comparison here, but just a couple quick observations:
These things are HEAVY. Having 15 bars the same thickness as Weber Summit grates which "only" have 13 really puts on the pounds.
Dave obviously has plenty of experience shipping and maxes out the USPS non-weight restricted "flat rate" packaging. Not as elegant as BBQParts but enough bubble wrap to make it work. They are tough and appear to be perfectly fine.
I pulled out the same magnet I have been using and you may be surprised to hear that these rcplanebuyer grates also show just a very slight magnetic attraction. So, a number of the better stainless rod grates all show this characteristic. I have to conclude that as George posted earlier, the process of making 304 stainless grates, especially with heavy welding to connect the bars, creates a very mild magnetic attraction even in pure 304 stainless. So, Qlimetal, Hongso and certainly US made BBQParts.com cannot be dismissed as not being true 304. On the other hand, other "stainless" grates grab my magnet with a whack. These are NOT 304 quite obviously.
This is going to be a really interesting comparison
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! Give me some time and I will do my best.
p.s. Having been able to look at rcplanebuyer grates in person I am now about positive that the Craigslist grill in the other thread I started about in "rcplanebuyer grates in hiding" DOES have his grates and flavorizer bars. The seller's price is too high, even with these, but I plan to keep an eye on it to see if he caves in to something more realistic. Grabbing a set of grates and bars to use on a nicely restored grill could be a big plus.