Welcome to the forums.
The DP will probably be much better as far as ride quality and handling.
I'm sure you seen the price differential between the DP and the gassers. The question I answered for myself, is the handling and ride worth the extra expense of a DP. For me, the answer was no.
Given the age of the two F53s your looking at, I submit that the handling and drivability is acceptable, provided three items are complied with. Check these on your pre-purchase..
1)
Cheap Handling Fix (CHF) - This is a simple adjustment of the torsion bar (sway bar) to firm up the side to side motion.
2)
SHock absorbers - Given the age, I suspect the shocks need replacing. I opted for the standard Monroe shocks. This was a significant improvement over the worn out shocks.
3)
Front end alignment - Verify / adjust that the front end has a slight toe in. no toe, or toe out contribute to handling instability.
If you opt for the F53, don't spend any money on aftermarket suspension devices until you've done the above three items, and then re-evaluate if additional add-ons are really needed or worth the expense.
If you're interested in a lot of F53 stuff, there is a sub forum here, AND, I also documented most of the work I've done on mine on my blog site.
http://www.1999southwind.com/
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