I have an order for RM but ST looks great too.
I'll be able to play ST a lot on location and think ST will be in production a long time so I can wait and see, if it's great then I can pick one up in a year or two. I just got SW premium which has been out for like 2.5 years feeling that ST will be around whenever I decide how good it is. Also if RM takes 8-12 months that ok because I don't need to buy two pins in such a close time period.
I have no idea but just started watching both series and just like 4 episodes each, RM is a lot more colorful and funny and ST is a lot more dark and serious.