Saying that X POE is "too much" or creates "too much drag" kinda ignores all the differences in the ratchet mechanisms themselves. There is a huge variety of mechanisms, some work well, some work better, and some might not work so well with a higher POE, whereas others work just fine.
That said, I run Hopes with 24 POE and for general XC riding have never thought "I need more". Singlespeed buddies running I9s love the higher POE, and I could see that having more, especially when running low gears like the 22/32 would make it nicer, but it's never stopped me from riding, so I wouldn't get too hung up in the numbers, just like megapixels on a camera. Tells only a small, small part of the story.
As for the BHS hubs, I've built several sets but so far not for myself. Have a pair of road hubs that I'll get around to building for myself at some point, and the quality seems very high, but it's easy for hubs to be high quality when they do nothing but sit on the workbench.
Been really happy dealing with BHS although they are a bit slow on the customer service now and then.