RNP is indeed very transparent while the RNLA has much more character. I own both and the RNLA gets used more often (on the way in for vocals and sometimes bass).
I just ordered the Tonebeast but I don't know when I will receive it cause there was some kind of clusterfuck between the bank and the vendor... In the meantime, I can tell you why I chose it over the WA12. I want to be able to control how hard I can drive it without overloading the interface's input, the same way I can do it with my Pre73 DLX. I think that's the whole point of having a colored kind of pre. It won't make a significant difference over a transparent if you don't drive it hard. Just my opinion.