The X5/X6 is still unclear if they are legit/ to be trusted, only one prototype review so far.
Best bet is to wait for Sidehack to release his pod and S5 upgrade.
Not there yet, but he's selling a USB stick with 2x BM1384 chips to funds dev.
He received sample BF chips from Punin ( Head of Product Development at BitFury )
I expect couple of weeks before been able to order those.
Quoted from Sidehack
The short-term projects are
2-chip stick using BM1384, wholesale price about $30, estimated 15GH/5WDC
10-chip BM1385 pod, wholesale price about $70, estimated 250GH/60WDC
Longer-term projects are
2-chip stick using BF16, wholesale price around $40, estimated 60GH/5WDC
11-chip BF16 pod, wholesale price around $125, estimated 650GH/75WDC
33-chip BF16 S1/3/5 refit board, wholesale price unknown, estimated 2TH/200W