Perhaps a disclaimer is needed?
Yes, Steve, apples ARE different from oranges.
I didn't post the cost for an '81 300SD radiator for any other reason other than as a comparison of pricing, and the simple fact was, that I couldn't get an online quote for an '80 on the weekend. OK?
I didn't intend to even imply that it bore any more resemblance to an W116 radiator than to a TREE! Their damn search engine simply didn't go back that far. I also couldn't get a quote from MercedesShop, or MegaParts either! I did just get a quote from The Benz Bin website for you, Tref, and it was: Part # 116-501-24-01, Radiator, New, List - 730.00 Your Cost - 620.50 Each.
Now, I also must strongly disagree with Steve's quote:
"...when I don't know what I'm doing I always differ to the highest cost item." STEVE! High price doesn't always equate to high quality...
There have been many times when I thought that the dealer's price for an item would be higher than aftermarket, I found out that I was wrong, and that the dealer did have the lowest price for the part. There have ALSO been numerous situations where I have found that the "stock" item wasn't any better, or even in some cases not as good as the aftermarket one. I don't buy cheap crap! Whenever I have, it has ALWAYS come back to bite me in the ASS!!!
So, here's my version:
When I Don't Know What I'm Doing, I Do Research, Ask Questions, And Make DAMN Sure That I Know What All Of My Options Are! 
But my Mercedes had a non-original radiator in it when I bought it, and I'm not about to pay $500 for an OE radiator to replace it, unless my research shows me that there is a major significant difference between the "Behr" brand and the aftermarket one.
BTW, for my car, I can either buy an OE radiator part # 126-500-35-03 from The Benz Bin for $346.79, or get an aftermarket copy of that one from them for $190.22. I'll need some details, but if these are the same except for the brand name, I'm buying the less expensive one.
And at the risk of "making another friend", I'll also disagree with Aaron's contention,
"Remember, if it's not maintained with genuine Mercedes-Benz parts, it's not a genuine Mercedes-Benz!" Personally, I think paying for a nameplate is foolish unless you're restoring a collectible vehicle. And, for some people, even the cost of a $500 part or repair may be beyond their budget. We all have situations where something has to last a little longer, be replaced as inexpensively as possible, or corners must be cut just to keep the vehicle on the road until we can get to where we can afford to "fix it right". If that wasn't the case, we'd all go directly to the dealer for all services and repairs, and there would be no need for this forum, or MercedesShop.
I am a VERY careful shopper, and I strongly suggest that everyone else is too. I would NEVER suggest that anyone, how did you put it, Steve?
"just go to Radiators are US mailorder and purchase a POS with half the tubes, half the fins and a third the weight for CHEAP". On that, I couldn't agree more.
But is what you say about this the facts about
these particular radiator outlets and their products? Or are you just postulating that they are low quality? I don't want to steer anyone into disaster, I'm just offering some alternative choices to fellow members who may be on a tight budget. I'd gladly defer to your factual experience...
Steve (and Aaron), we rely on you to give us the "factual" benefits of your wisdom and experience as regards the maintenance and repair of these vehicles. Please, with all due respect, I would prefer you make comments about a particular sales outlet, product, or anything pertaining to Mercedes from factual data to back up your statements. I want to be able to rely on your word as gold.
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