Wow, the Dinan Strut bar is $600!!! Inflation.....I was one of the earlier X5 owners who got the Strut bar early and I don't think I even paid half that price....Guess, the cost of aluminum has gone up.....

Anyhow, to answer the question, I have always been a big believer in strut bar.....Reason I got it was that I gone from 18 to 19" wheels and my experience with my last BMW E30 that potholes and struts do not get along....My strut tower in the E30 did bend a little bit....

Now, the X5 is built really well and it is a solid car.....Will it make it more solid....well, think of it this way, if you happen to hit a pothole, it would less likely that one of the strut tower will bend/move....If you doing some really hard cornering, the strut towers will be less likely to bend or turn and the handling will be more predictable.

Now, comes to the question of price/benefit ratio....only you can answer that.

Also, I also installed the Rogue Engineering camber plates which essentially does the same thing as the Dinan's one but much more cost effective. That also improved the handling as well by adding another -0.5 degree of camber for the front tires.

It all adds up, but I surely can do more tougher cornering more predictably since I added all these things and I personally thought it was worth it.

Interestingly enough, all the newer BMWs (E90 3-series, E60 5-series, Z4, X3) all have some extra strut support nowadays and also, my E46 M3 has a standard strut bar as well. So, even BMW thinks it helps.

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