Last I checked awesomeminer is also a vnish re-brand. At least the S9 version they advertised was.
You are right about this one, in fact, Patric from awesome miner himself confirmed that
Of the 2% mining fee we are actually getting half of it. So we do benefit from customers that go for the Awesome Miner firmware. This is also the reason why we can provide product support for it and also integrate it well with Awesome Miner. Users of other Vnish firmware do get most of the features as well, so your point is valid that we do give away features to a larger user base. Some features like setting Mining Profiles via Awesome Miner is exclusive to our brand of the firmware. We could make more feature exclusive, but we are also trying to be nice to our customers and respect what decisions they make.
The dev fees on Vnish website are as follows
Dev fee 1.6-1.9% only for S9/T9, 2.6- 2.9% for S17/T17
awesomeminer's fees for S9 is 2% or 3% (without consuming awesomeminer license), for S17/T17 the fee is 3%, so that's anywhere from 0.1% to 0.4% more for awesomeminer, if you use awesomeminer to monitor say, 100 miners, then you have to pay 700$ for the software, so one should do the math and see if the difference in fees is worth the license and the features that awesomeminer provide which Vnish doesn't. If it makes no economic sense, one might want to stick to Vnish, I personally use awesomeminer and I count on it big time to manage my gears, so I wouldn't mind paying a little extra, but that is just me, everyone should run the numbers.