The OpenDRC-AN is a bit more expensive at 299 and according to the specs it has 2 inputs, 2 outputs. There's only one plugin for it, the OpenDRC 2x2 plugin. There are level management for all inputs and outputs, plus two FIR blocks that can be used to implement various room correction algorithms. However I don't think REW can compute the FIR coefficient for the OpenDRC platform; in that regard integration with REW is more limited. I agree this looks like an awesome product though, but it's more aimed at full-band room EQ using the OpenDRC framework. MiniDSP sells additional software such as AcourateDRC ($75) to compute OpenDRC coefficients. If you're more of the hacker type, it's compatible with the (free) Python Open Room Correction (PORC) open-source software library. EDIT: it's also possible to use the rePhase free open-source software to compute the OpenDRC coefficients.
Note that I have no first-hand experience with the OpenDRC products from MiniDSP nor do I have any with the OpenDRC platform; I'm just trying to outline the differences between the MiniDSP and OpenDRC products.