Backert Labs Rhumba preamp

I am thinking of going to an active line stage for sometime now. I have a separate thread for that and people have suggested some good choices. The reason for this thread if that, while I have all along said that  don't want tubes in the system, a few have convinced me that I should try tubes in the system, especially with ProAcs.
With that said, I researched a few tube preamps, that have XLR out and the Backert Labs Rhumba is the one that has only 2 tubes, which makes me comfortable to "deal in tubes".

I would like to hear from Backert Labs Rhumba owners who moved from Solid State preamplification to this preamp. What are the differences you heard? Any improvements?

I read a review on the Stevehoffman forum and the user mentioned that there is a "hum" in this preamp. This bothers me and hence I decided to check on this forum, if anyone has experienced this with the Rhumba in their system. One poster on this forum also confirmed the "hiss":

So I was wondering, if there are any users who have recently purchased this preamp and what is their experience with the hum/hiss issue.

BTW, I blame Ralph of Atma-Sphere, Almarg  and my dealer for making me consider tube amps :-) Can't believe I am creating this thread.

have anyone upgrade from a Rhythm 1.2 to Rhythm 1.3 ? may i ask what are the main difference you heard? Thanks, 
@philipwu, Not sure if it is helpful but I upgraded from the 1.2 to the 1.3 Extreme.
hi, yes. i would appreciate your help if you like to share your experience with your new 1.3 Extreme. What are the new improvements that you notice? how long have you been burning in this new preamp ? Thank you for any info. 
Would a Rhumba 1.3 mate well with my Bryston 4B3 amp ???
Been looking for that magical pre-amp for 2 years now !!!
The output impedance of Rhumba is a low 75 ohms. Based on what @almarg once told me, this will match with your Bryston 4B3 amp, which has an input impedance of 30k Ohms.
Check this thread: