What specifically do you mean by "Bromide"? Do you mean "Bromine"?
I've known of a few manufacturer's that will say that the use of biguanides as a sanitizer will void warranties, but I have never seen bromine specifically voiding out a warranty. If there is a manufacturer that voids warranties if bromine, its news to me.
Pump seals can degrade by overall water chemistry mismanagement. My service dept. would put a loose % of hot tub motors that burn up due to seals failing at 80%. The seal fails, allowing water to enter the circuitry and fry the pump. (We use Balboa and Waterway motors- Both are noted in the industry as quality brands).
Jets can degrade regardless of the sanitizer: The plastic in the jet is what degrades but many erroneously claim its the ball bearings. The bearings fall out due to the degradation of the plastic- which all jets are made out of. Regardless of your position on this- Its all traced back to water chemistry imbalance. pH habitually at elevated levels causes metals to corrode (pulled from its source), and pH habitually at lower levels will cause metals to deposit (the 'sandpaper' feel on the tub's shell).
There are many that do use the liquid chlorine route in this forum. I will let them speak to the merits of that particular method.
Granulated chlorine, bromine, and mineral sanitizers (Spa Frog, Nature 2) are your most common sanitizers in the industry and I have never heard of them voiding warranties, outside of standard catch-all water mismanagement voiding warranties.
Other methods may actually feed into the issue in which you speak (again- noting that pH imbalance is the main cause): Tabletized chlorine emits a gas that can cause issues, and if the tablets are put in the filter area every time they're added to the tub, you're getting a caustic level of chlorine directly being fed to the motor which will cause parts to degrade at an accelerated rate.
The same can happen with liquid chlorine, as too much chlorine added can cause a huge spike in the chlorine level (1 gallon treats 10k gallons, so there is really no room for error in measurement as most tubs are 400 gallons or less), especially if added close too the filter intake (as noted in the preceding paragraph).
I hope this helps. Good luck moving forward.
