Never heard of 'em...and I got my first SKS in 98ish.
I believe considering all we have read over the years about Kivarri and Murray. Considering they both will contribute to gun boards regarding discussion of what they do, vs. these guys who nobody has heard of, and comparable pricing....I would lean towards K or M.
If these guys were offering thirty/forty dollar jobs, perhaps I would chance one to see what happens. There was a guy on eBay offering services as such for around $50 + return shipping...still too spendy to risk it for someone you never heard of.
I have seen the AGI and Sailor Curtis (?? stupid memory ??) videos, and I have attempted to do a couple, never being quite satisfied...and once having to replace a sear. It's a fine art, while the artists still exist, I think I will let them do the work in the future.
Perhaps you could convince them to do one pro-bono for a recommendation among board users?