Hi Brunomarcs. I was thinking of trying the Rogue RP7 to upgrade the Freya +. I am really wondering how much improvement it's going to be and maybe not worth the trouble. I like all the features of the RP7 or 9. I really like the Freya + in tube mode best and I have upgraded my tubes to the CBS Hytron which cost almost as much as the preamp. The tubes made it a lot better I thought. I didn't go back and forth a lot but my initial impression was wow. You might try some better tubes there is a lot of info on tube rolling in the Freya + out there.
I also own the Benchmark LA4 which is really good too right up there with the Freya. The Benchmark is a cleaner leaner sound. I still overall like the tube mode on the Freya slightly best. I was thinking there has to be some big bad tube pre Lamm, CJ, AR that is going to be a lot better than this little guy.
Anyway amazing and lucky we can get such a great product at a low price. Good job Schiit