Clean installation took many hours. Problems:
1. Need downgrade system config (as example initrd modules syntax, I forgot about it)
2. After first 'guix pull' - error as in Thread "Error: system: command not found." Fixed with repeat guix pull.
3. Initial 'system reconfigure' fails at final (error with retrieving one derivation - "Network error"?), repeat wit --fallback.
4. Initial 'guix pull' in non-root account, using one processor core (this was necessary) took more than FOUR HOURS!
5. A lot of questions on building heavy packages from source and of the final set of packages (mariadb? Is this really the right system package??)
I will not risk repeating this! =) But maybe something could be done more correctly? Any recommendations?