@rooze , Sorry for being late to your thread. I think lewm and rauliruegas have a lot to offer on this subject. IMHO the best solid state units easily dwarf the best tube units for accuracy and quietness. The Moon phono stages are exactly the type of design I look for, well built and unadorned with rarely used switches, circuits, etc. With units like the CH and Dartzeel you are buying a bunch of capability you will never use. So why pay for it. I would be surprised if the Moons did not equal or surpass these units. My own feeling is that if you are going to use multiple arms and cartridges then you should use multiple phono stages suited to the individual cartridge.
There are two basic types of phono stages, current mode and the more common voltage mode. IMHE cartridges with an impedance less than 3 ohms will definitely perform better with a balanced current mode unit Like The Sutherland, BMC or Channel D phono stages. Above 3 ohms, if a cartridge has an output greater than 0.5 mv, current mode will work fine. Above 10 ohms a voltage mode unit is mandatory. Some phono stages will do both like the Channel D units. The best sound I ever heard coming from a turntable is from a Lyra Atlas Lambda SL through a Channel D phono stage running in current mode with digital RIAA correction.
Signal to noise ratio is critical. Even small amounts of added noise can play havoc with the sense of reality. The Moon units are SOTA in this regard. The only phono stage that I know can do better is the Channel D Seta L20 which is pushing $50K, not what you would call a value. I have an Ortofon MC Diamond, 6 ohms with an output of 0.2 mv. It struggles through the channel D in current mode because the signal to noise ratio is not good enough. It would positively sing through the Moon units. The Lyra and a MSL Signature Platinum perform brilliantly so I plan on selling the MC Diamond. As an all around phono stage for someone who is not interested in digital RIAA correction the Moon units are unbeatable at any price level. I also believe that the absolute best sound comes from a very low impedance cartridge driving a current mode phono stage. The Channel D compromises signal to noise for a wildly wide bandwidth, 5 mHz! This approach only works with a limited number of cartridges until you get to the Seta L20 which will mate with any cartridge but at a very high price.