I also use the WeatherTech cargo mat, my first experience was my wife's 2002 CRV (I got the mat from a guy who sold his car). I even had a small gasoline spill on the mat (from a car refill can) once. It held the gas, protected the car. It didn't melt or alter the mat at all and it cleaned up fine - no latent small after a day.

I was convinced. I've put the same in my E53 X5.

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2002 Euro X5 (E53) 3.0 diesel (M57)
5 speed manual with UUC short shifter.
Pre-xDrive NV125 transfer case (chain & gears).
Factory Xenon headlights, Spyder LED tail lights
Updated vortex crankcase breather.
Motorsport dead pedal, factory fire extinguisher, factory first aid kit, factory F&R mud flaps, factory PDC

Bilstein B6 shocks F&R
Redline oil has replaced "lifetime" fluids (F&R diff, manual transmission, transfer case and P/S).
Dimple magnetic drain plugs in all compartments.