The risks with Qlaira are likely to be lower as the estrogen dose is lower than nearly all other BCPs (only 2 days of 3mg) and it's not synthetic, so again, less potent. It is for this reason that I am allowed it, despite my dad having had a stroke at a young age and me getting migraines (occasionally with aura). To be honest, the estrogen I take is similar to say, Femeston, so it worries me no more than when I took HRT.
Given that many pills have the same estrogen but different progesterones - with different risk levels associated with each generation's - makes me think the progesterone plays a role in the risk factor too? (Either alone, or in the way it interacts with the estrogen). Qlaira has a 4th generation progesterone called Dienogest. Research on it is sparse, mainly because it's so new (and expensive, so therefore less popular - though as a BCP, you get it for free!) but from what I can tell, it's very much an 'average or lower' risk - hence reason I was prescribed it, but the doctor would not let me have a conventional pill. It's not a brand new product, just new to the UK . It's far more common place in France and the US.
As I have said before, it is not the perfect product. I suspect such as thing does not exist. Spotting was an issue for several months and I do have the occasional blip when I am convinced my own hormones are still playing silly buggers, but overall, it's massively better than anything else I have tried.