My
advice, from my personal experience with wx, sailing and routing:
If you think you want a router, get one who has experience in the required / specific geo area. Or someone with global experience.
If you have onboard someone with good level of wx understanding, invest in hardware/infrastructure and do your wx routing onboard.
If you are sailing in the good season, away from major wx nuisances (high latitudes lows, low latitudes tropical systems, ITCZ) then forget about a router.
Avoid routers who are not sailors. If you do need help, you want to talk to a person who understands the reality and limitations of extended ocean passages.
Regards,
barnakiel