Advice needed, MC cartridge for SpaceArm?

I own a Nottingham Spacedeck/Spacearm along with a ARC PH2 phono preamp and Clearaudio Virtuoso cartridge.

I have been most satisfied with the above setup for about a 1 and 1/2 years, rarely listening to CDs anymore. This is my first vinyl setup in 20 years. Now, I have come down with upgraditis. (uh oh)

Have decided to upgrade the PH2 to ARC's new PH5 phono preamp. This will allow me to try a MC cartridge for the first time. Question is, which one? My system is heavy in tubes, tubed PreAmp (Ref 1) and tubed monoblock amps (Rogue M120s Magnum) Speakers are Soundlab electrostats.

I am leaning towards the Shelters 501 or 901 based on internet research but have not ruled anything out. My listening preferences are Classical / Orchestral first. Behind that would be Jazz/Country/rock/pop / whatever all equally weighted. Any ideas as to the MC cartridge that is the best choice? Would like to keep it under 1500.00 It is unlikely that I will be able to audition most cartridges where I live.
Well, my friend Ozzy62 went thru this whole exercise just a few months back! I hope that he sees this thread & chimes in. Basically, he tried the KOntrapunkt-B (the more expensive one), Shelter 501 & the Benz L2. I think that he might have tried a few other MC cartridges but I cannot be sure. ANyway, he selected the Benz L2 over the lot ($800 new). His personal tastes aside, I believe that the medium compliance Benz L2 was a much better fit for the unipivot Spacearm. The Shelter 501 is a low compliance cartridge & it is likely to not match up the Spacearm. There are tonearms that can take low compliance cartridges but I do not think that the Spacearm is on that list!
Hope that this helps.
Bombaywalla is correct that I do love the L2. And I did try several other cartridges on the Spacedeck, but not on the Spacearm. I had a Bluenote Borromeo for a while and it did not like the Shelter 501 or the Kontrapunkt B. I finally ditched the arm because it was so finicky and bought a Spacearm. The only cartridge I have tried on it is the Benz, but this is a great match. I wish I had the opportunity to listen to the Shelter on the Spacearm, because this might have worked beautifully. Although the Spacearm is indeed a unipivot, it is somewhat stabilized at the pivot point, unlike most others of this design. I know 4yanx had this combo for a while, so hopefully he will join in on this.

You might also consider a Dynavector 17D mkII - same price range as the Benz L2. Hard to lose with either, both are fine cartridges, and I have heard both sounding good with a Spacearm/Spacedeck. Same guy that had this combo mentioned that he preferred both these cartrdiges over the Shelter 501 though his friend preferred the sound of the Shelter, while he preferred the sound of the Dynavector. In both cases, the Benz was the second choice.

I have a 17DmkII and really like it, for what that's all worth...
I have a friend with a Space Deck and Space Arm. He wanted something more neutral than his Grado and more resolving than his Denon.

I sent him my Shelter 901 to try (that offer is open to all A'gon members by the way, just email me). But I also told him I thought a medium compliance cartridge would be a better match, and that for his musical tastes (classical) and sonic preferences (neutrality) a ZYX would be hard to beat.

He bought a ZYX R100 Fuji and is very pleased. It outperformed the Shelter 901 on his rig, as it does on mine.

Dynavector and Lyra should also be suitable matches for a Space Arm. I haven't heard them so can't offer any comparison.