OT, having played on RA for a full week now, I have a few things to say.
(Everything below is from the perspective of playing in Alsius on RA.)
Apart from what all Irsh said being true, I faced problems initially because of lack of commerce tab in warzone. You find more more at realm gate than at CS sometimes because they want to buy/sell

And if you don't get into a kind clan which can lend you good items, you're in for a long term play with market items or drops.
Because good items are traded only in mags and mags are a thing that you find once in blue moon at RA. There is a separate sect of people there who do nothing but mag hunt all the time they're on lol. Without special mag-hunts, I usually have around 20-30 mags by lvl 48 on Haven. But I got like 4 mags on my lvl 47 toon in RA
Also, RA is not for the chatty types. That's a very good feature of RA's populace. They talk less and fight more. I know there are a few people who come online just to talk and chat with their virtual friends and the community (nothing wrong with that I guess). But for people like these, RA will be not as entertaining as Haven is, at times.
And ganking. God. I tried to grind in trelle beach at lvl 46. I got ganked 6 times in 10 minutes at some times. In Haven, I rarely get ganked at trelle beach. As errei mentioned, RA is a huge target ground for hunters and marksman.
Overall, to conclude, my experience on RA was a very refreshing, enthusiastic and encouraging one. I'd have left for RA already, but I don't want to grind all over again and I don't want to leave my clan and Alsius community on Haven.
So, yeah, if the servers are merged, it'll be like a dream come true for me.