I am not sure about a bitmain decred miner
I was going to say "it doesn't exist" but perhaps "they don't sell one yet" would be more accurate.
and Innosilicon does not have an Eth miner or a B3 miner
Bitmain ETH miner (E3) is less efficient even than some GPUs, e.g. 1050Ti, so Innosilicon could probably beat it if they wanted to.
Unfortunately Innosilicon as business sucks so badly that these efficiency gains don't really matter much. I know you said it's not about the price and all the other things but Bitmain the horrible pigopolist does those things better and they likely don't feel they need to compete for every watt. The difference isn't that big between the T2 and the S9(i), which I think is their main revenue source.
and the t2 turbo now does 18.1th at 1350 watts
the s9i does 14th at 1400 watts
and a new miner from pangolinminer due in sept 2018 the m10 will be doing 33th at 2150 watts
https://pangolinminer.com/2150/33000 = 0.0651 watts per gh the clear cut leader
I know I can order 2 s9i's today for 1120 use my last 2 100 dollar coupons and pay only 920 for 28000 gh
but with gear that is doing 0.066 vs 0.099 I have to pause and think what is best here.
I owned a pangolin M3 it was okay and was shipped quickly to me.
loud and hot but many miners are just that.