I like Inawera. I think many of (but not all) their tobaccos are top notch interesting flavors, their custard is The Best, their Shisha Strawberry is my favorite strawberry (of the 17 different strawberries I have), and their Lime is the cleanest, most realistic lime on the planet. That said, I think some of their fruits are pretty terrible. Flavorah's fruits are superior to many of theirs.
Hangsen can be hit and miss...Outstanding tobaccos, all of the ones I've tried have been top notch. Their Vanilla, Irish Cream, and French Vanilla Ice Cream are excellent, but I don't care for their blueberry, raspberry or any of their fruits. Also, Hangesn's "strength ratio" seems to vary wildly, which makes it more challenging to get percentages right in mixes. For this reason I don't have a huge inventory of Hangsen, I use their tobaccos and above-mentioned vanillas often.
"Usual Percentages"? My best advice with INW is Always Start Low. Hangsen, you've got to experiment.