Need Advice on WDH for 2720SL

[Burquena]

I just recently purchased a 2008 2720SL - thanks to all of you on this forum (where I have been lurking!) I felt well prepared to make the leap! I am a real newbie, and I have tried to research the WDH issue and I feel like I now have so much information I am more confused than ever!
I am towing with a Dodge Dakota 4.7L v8, TM has A/C, no other major additions, although I'd like to add solar in the future. When I carry my inflatable boat, outboard, etc. it is stored in front of the rear axle in the truck bed, but now that I will need to carry water for the TM, it will be farther back and will add to tongue weight (correct?). I have not been able to take it to a scale yet, but would guess it will come in close to what others here have posted.
My question: if I go with a WDH at 1000# over one at 800#, will it be too much when I tow without the additional weight? (When not going to the lakes, that is). I am concerned about the ride being too stiff as mentioned in some of the posts.
Thank you!