OK.....story changed. Glad you aren't street racing. I witnessed an Audi S4 swerving in and out of lanes racing a Nissan 350z on the highway today. He almost lost it.

Congrats on the new 4.8i. You were told correctly, BMW has great SUVs.

If it's a base Grand Cherokee with a hemi, you are more powerful and have better handling. I assume you are a decent driver, so it shouldn't be too hard.
A Grand Cherokee SRT-8 is a different story though. It may not handle as well, but it will completely whoop you in the straights. If they are a good driver, you probably don't have a chance.
Congrats on the new bimmer and BE Safe!!! Make yourself familiar with the limits of your new X5 before you try anything.

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