I guess I'm like a number of others here: I came up the PADI route (OW, AOW, Rescue, DM etc.) initially and then swapped to an organisation that better suited my diving needs and aspirations - TDI, which, incedently, I've found provides a better all round 'capability' for diving in UK conditions (temp, viz etc.).
What I will say (and NOT wanting to start a flame war here) is that, ironically, neither PADI, BSAC et al wanted anything to do with Nitrox (let alone other exotic mixes) when it was 1st introduced. Now that they can see a market for it they're in like Flynn - not surprisingly.
And aren't we missing something important in this inter-agency review? I don't know whether it's already been mooted (apologies if it has), but the diver training agency is NOT important (as long as it's a recognised body): the most important thing in teaching a diver good and safe diving practises (be that recreational or technical) is the Instructor in question.
Dive safe all - always.