No, only you can decide if it is worth it to you. Dinan parts are generally high quality, well engineered, and expensive. You aren't going to see any appreciable difference in hp if that is your only criteria. People buy parts such as these for other reasons, though, and for some the cachet of having something more exclusive is worth it.

I have a Dinan throttle body and MAF sitting on my coffee table. The tb is MAYBE 2mm bigger, and if you remove all the checkered crap from your stock MAF housing, it too is about the same. Buy an Eisenmann or Supersprint exhaust, An AFE CAI, mod the MAF housing, and get a tune from ESS or something. You'll be better off.

P.S.- I'm on vacation, but when I get home I'll send pics for everyone to laugh at.

P.P.S.- JCL, the Dinan TB has a freaking rubber band on it to cover the mods done to it (I have confirmed that it isn't just mine). They do next to nothing and charge A TON OF MONEY FOR IT. Unless you get a used one for cheap, not worth it.

P.P.P.S- Previous owner did the Dinan stage 1 tune on mine, couldn't tell a difference. If I were you, CAI and exhaust (which will not void a warranty) and call it a day.

Just get a 4.8is. You will notice that difference.

Nice, but not an option.

My warranty covers all work done at my dealer, which leads me to think dinan only. I'm leaning towards exhaust and cai. Anyone have a video of a facelifted 4.4 with dinan exhaust? I know there are a bunch of the 4.6 or 4.8 with it just haven't been able to find one of the 4.4

As for exhaust, check this thread for Eisenmann vs. Dinan exhaust

Dealers don't have warranty issues with aftermarket exhaust. I have taken my cars with Eisenmann exhaust for years to several dealers and no issues.

Thanks for the forum link LeMans, but won't my 4.4 sound quite a but different than those 50i's and M///'s??

The dealer warranty issue for me only pertains to the fact that my AFTERMARKET warranty states that all performance mods must be done by the BMW dealer. From there I went ahead and took this to say that since BMW dealers would only install Dinan parts, that that was my only option. Is this true or will they install other brands as well?

A BMW dealer will install any part you wish. However, if you read the Magnuson-Moss Warranty Act, the burden of proof lies with the warranty company should anything fail on your car.

Here's the Eisenmann: www.Sport-Wheels.de BMW X5 4.6l Eisenmann Auspuff Exhaust - YouTube

Here's the Dinan: Dinan x5 4.6is - YouTube

I've heard both in person and prefer the Eisenmann, FWIW.

I think you'll find that what is commonly called an extended warranty is often actually a service contract, regulated under state rules governing insurance, and therefore not subject to the provisions of Magnusson-Moss.

The link was not for sound. ;)
The link was to show the pics in that thread which display the build quality of Dinan vs competition. Dinan has clearly the worst build quality of the 3 exhausts discussed in that thread.
And those are pics for X5 M, exhaust of which is "supposed to be built" even better than E53 X5 4.4i.
I do own a Dinan BMW, but when it comes to exhaust others are better than Dinan.

So what is the appropriate pricing for the Eisenmann? I have seen them listed for over $2k. I am all about quality but I just don't see two grand in any exhaust system not made from titanium. They must be impossible to find used as well.