Anyone own one of these preamps ?

I briefly owned the LA-4 and agree completely with @zlone  This preamp is very detailed and clean, but sterile and uninvolving. Didn't hang around long.

An added note:  the RP-9 comes with a hefty metal remote that allows you to alter the balance of the two channels, in addition to other functions.  I have owned the RP-1, RP-7 v1, and now the RP-9 v2 and have never had an issue with channel balance with any of the preamps.

 Also, the folks at Rogue Audio are very responsive to questions.  We had a “power flutter” here—the power going off and on several times in a few seconds—and then my RP-9 would not turn on.  A call to Rogue got me up and running again with zero issues in less than a minute; I simply had to cycle the master on-off switch h on the back of the unit.  The front on/off switch simply puts the unit in the standby mode, and the RP-9 needed to be restarted.

+1 For the Anthem STR. Read a review a few years ago talking about “Anthem Fanboys” I suppose I’m one of them. 👍 Had mine three years. In my rig has a neutral sound in an all solid state system with Sound Lab G7-7C electrostats. Feature-rich. Solid build quality. Decent price point. Lots of connectivity options (except HDMI, which doesn’t break my heart). Lots of options on their turntable input, tho I can’t comment on the sound. Good phone support (called about ARC). Online documentation is good and, with ARC, interesting as well. The AV passthrough feature sealed the deal for me since I use my gear for both two channel music and movies/TV. They use relays for this, so you can hear them click when switching modes. 
 

Only inconvenience is that my listening position is about 8 feet from my rack. You configure the STR with the remote, but I can’t read the screen from my seat. Wish they had an app for that. Also, if you use ARC room correction, it runs onboard the preamp. It’s DSP, so you measure and load configuration files from a laptop or phone. When I stopped using ARC after getting new speakers, I couldn’t find a way to disable it in the onboard config. Had to fire up my old laptop to remove the configuration files. 
 

Overall, a Happy Camper. As always YMMV. 

@mazian - personally, I didn't care one way or the other what the remote was made of; it's that size does matter if you don't want to keep misplacing the thing, and this teeny-tiny remote is always playing hide-and-seek. It's way less than half the size of the smallest hi-fi remote I'd ever seen before. 

The Benchmark LA4 is my end game pre. I tried bunch of them and when I put this in my system it was instant love. Who wants to hear their pre, I certainly don't. It is completely transparent to source for which I am completely grateful every single day. It's utilitarian looks are a money saver. The remote, volume control, switching, and connections are all first class. Pair it with the DAC 3B and enjoy the synergy. Also service is the absolute best!

If you only like chocolate milk then this is not for you. Fresh clear cool/warm water is what we were designed to drink. To each his own.