Hi Skellz,
Definitely keep the SLS !! I replaced my original bags with new ones - as Jason says it's a very easy and quick job. I got mine from Land Rover Parts, Accessories and Spares From Brookwells
I also upgraded to Koni's and the ride and handling is great.
With the long range tanks and towing you'd have to put pretty tough springs in the back to keep the height right - but your ride/comfort would suffer when unladen. Thats why SLS is so good - the spring rate automatically adjusts to the load you're carrying so you retain the supple ride when laden or unladen.
Hope the upgrades go well.
Cheers
Simon
2003 D2a TD5, ACE, SLS, Vienna Green.
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