those are the ones I have seen as well.
I figure they are ok, but you will find that they sell for $100-$130 no matter what.
I've seen some in the JC Whitney Catalog, that look just like those, but with more selection of tips, for I think $125 or $135, so as you can see the price difference is negligable.
I myself would rather order it from the jc whitney catalogue. Than that guy on E-bay.
I had bid on one, and my final bid was like $95. The guy E-mails me after the auction becauseI didn't win it, and offers to sell it to me for $115. I told him maybe, and had him send me the order form and such so I could look at the order form.
I talked to him and decided if I was going to buy it, I'd meet him halfway at $105. I then decided that I would go to a proper shop to get a muffler and work done, because I can get a great deal on the muffler with installation, and have it come out to be very nicely priced, and I know I can trust it. and get a better warranty from a local shop that builds custom exhausts.
I'm not saying that guy selling on e-bay is bad, but don't think you will get it for less than $100 at all.
'92 300CE - Sold
2004 C240 - C7 Wheels
2015 ML350 - P1, Pano, Ash poplar wood, Sport Dinamica interior, Running Boards Keyless go.