RRT-1 definitely has sharper, more defined hotspot then the RRT-2. I prefer the RRT-2 though because it's easily more pocketable (then the RRT1). The RRT-2 lacks a clip. Also, neither light offers a very low Low so if that is important to you, be warned. I don't mind the bright Low so much though as it's all concentrated into the hotspot with reasonable spill.
I have a smooth-reflector version of both RRT-1 and RRT-2, with XP-E R2s. I've heard there are textured RRT-2 lights out there so if throw is important you might want to be discerning. I've never seen a textured RRT-2 though so I cannot say how it compares.
I haven't bought any Jetbeam released since the RRT-2 as I've been put off by the troubles the RRT-0 and M2S initially had. My M1X and III-M have been very solid (as has the RRT-1 and 2). I have some concerns over the quality of Jetbeam heatsinking from other CPF threads I've seen here (lack of thermal paste, potting, etc); I'm new enough to this hobby that I don't really feel confident in my skill to assess how good my own equipment is. They definitely don't pot their LEDs like Malkoff!