Zach your the one offering up the custom parts... I say do what is easier for you and your time... I know building up bolt on sliders will take a lot of time. and a hole lot of extra effort..
I say go weld on.
Fabing/giging time will be less, time welding will be less, shipping weight will be less for the customer, and finding a local shop to weld them up if there welding inept shouldn't be that expensive or time consuming...
If you do start this up are you going to offer different materials, (DOM)?square or round pipe?
I would highly consider buying a set if the price is right.. (military discount