I missed the announcement of the Radial Firefly, just Googled it, neat product! They basically added a 12AX7 to their top-of-the-line JDV. Found one magazine review, which was excessively gushing with praise like most such reviews, but the writer did "let slip" that overdriving the tube doesn't sound so great, using a P bass. Also I haven't found any specs (even on the Radial site) saying exactly what is the slope or corner frequency of the low-cut filter; have to assume it is not low enough or steep enough for bass amp/cab optimizing. On the plus side, it does use an output transformer, which will likely help give that extra "sheen" to the tone, as well as blocking phantom power to prevent damage.
I actually doubt it will be a direct competitor for the REDDI, tonewise, but instead will compete with the Summit TD100.