I've seen those puppies and they're sweet. The ROI was 45 days. It's much more now that they're in the wild.
At current prices, they're too expensive, however.

Edit: I wonder if there's a jocker in the Baikal asics too. Now that monero is going to v7, I am very curious to see if the baikal asic is programmable (i.e. an fpga design).

In theory, if could very easily be just a bunch of super-fast memory tied to an fpga that can be *easily* updated via firmware updates.

If that is the case, it will take a little more tweaking to defeat them: I mean jacking up the memory requirements beyond what baikal has on board or changing the algo completely, and going with something totally different.