1. If you are using the tophat strut spacer, you will lose a bit of the factory ride comfort. There's not a big difference, I prefer it actually, it's just more firm.
2. The preload spacer has been mentioned as a no-no for Off Road optioned trucks from the getgo.
3. In order to reduce rake, you need a slightly taller spacer to compensate for the lift in the rear. Motofab 2.5 spacers give you an actual 2.5 lift which will get you to 25". The RL tophat only gets you just over 1.5" in actual lift.
Hope that helps you move forward.