Is Zoom whitening necessary for my sensitive already a1 shade teeth?

My 4 veneers on my front teeth need to be replaced. The dentist wants me toget Zoom whitening before. Im an A1 shade Ive used whitening systems in the past, prof trays to strips and whitening toothpastes,every method my teeth become very sensitive even if i leave it on for half the time.I assume Zoom would be even worse . He said if if I use 600mg ibprof i would be fine.Some of my staining is intrinsic from antibiotic use as a child but its not bad. What do you guys think is it even worth it.?