They are both great companies as mentioned above.
The only issue I have with both is that (as mentioned by awap) in the US they do not support DIY regulator service. That being said, I have never had any issues getting parts for both, but part of that is developing a good relationship with several my local dive shops.
Aqua Lung and Scubapro are the only two companies with a design philosophy that (most of the time) builds on the success of their previous designs and (again most of the time) the changes are cosmetic or minimal, unless they make a substantial technological improvement. This design philosophy provides not only well proven designs, but also parts compatibility that supports older models and reduces the need of large service parts inventory.
Other companies may be adopting similar design philosophy, but must are too new to have much of a track record. That is not to say that other companies don’t make excellent regulators, they just don’t have the track record.
Note: Poseidon is a unique case, they have the oldest regulator still in production (which is also one of the oldest single hose ever), but all their other regulators are unique and none share any parts commonality.
As to giving equal time to both companies… well I certainly do. My favorite (single hose) regulator is an Aqua Lung Titan (or Conshelf) first stage with a Scubapro Metal Balanced Adjustable second stage (109/ 156). I can’t conceive of a regulator combination that will produce any better performance, more durable, more reliable, easiest to service, easiest to find parts, and stock minimal amount of parts. To me that show that both companies make such good products that to get all the best features I personally need to take parts from both.