By Sylph.Hitetsu 2010-04-28 11:13:52
Your gear will change a lot as you level up, at the beginning you may want to look at cheap MP+/MND+ items. Later on however you'll need a fairy wide variety of MND+, INT+, Skill+, etc.
As far as Subjobs go, you'll definitely want WHM, BLM and NIN at 37+, PLD BLU and DNC all have some use aswell, though it's not as wide as the first 3. WHM will be your most used subjob (though personally, I prefer SCH as a RDM support job, most of the benefits of /WHM and more of it's own!)
I'm sure more experienced RDM's will come in and give a better idea of what to expect though.