Soundsmith - Hyperion vs lyra ETNA

I don't think you'll be disappointed with either.  I have had three main carts on my table for the past couple years.  A Koetsu RSP, a Lyra Atlas and a SoundSmith MIMC star and most recently traded up to a SS Sussurro.  
To my ears, the SoundSmith sits in the middle of the Koetsu and Lyra spectrums of emphasis. It is not distracting on the high end like the Lyra can sometimes be with its super realistic extension and it is not as romantic and groovy as the Koetsu. The SoundSmith carts do get out of the way in all the right ways.  Makes me forget about what cart is on  and enjoy the music.  You can tell you are getting everything off the recording without commentary. I really love how those SS low output carts sound. So quiet too!

Disclaimer...my system, my ears, haven't listened to the Etna. 

I have only listened to EMT outside my home so I can't tell you what kind of changes to expect compared to a Lyra or SoundSmith.   I do have the perspective of breaking a Lyra Delos. So what Bill says above is an excellent point about MI versus MC.  Much cheaper to repair the SoundSmith cart, plus at this level, should you ever need it repaired, Peter Ledermann will do it himself.

@dodgealum I also had the non-ES version of the MIMC star.  My initial impression was positive but I also felt like it sounded a little "closed in" for lack of a better term.  Very clean and low distortion but not the expansive soundstage I was used to hearing form my other carts. I'm wondering if this is why some people are turned off from SS carts? For me though, the clarity and focus of the MIMC made me continue to listen. Something great happened around 50-75 hours of playing time (hard to know for sure cause I rotate carts) and the MIMC became more expansive, super clear and just sounded very natural.  Its like a sonic magnifying glass was applied.  I started hearing lots of new musical lines in complex music. Master tape-like without hiss.  It was after I noted this breaking in that I became interested in hearing what the fancier SS carts could do.  

I traded the MIMC in for a Sussurro MKII ES and I've had it mounted to the same Mørch DP8 arm as the MIMC.  The Sussurro already sounds as good as the broken in MIMC. Not "closed in" at all and very low distortion.  Amazing channel separation, musical information and natural frequency balance.   I have maybe 20 hours on the new cart and I am hopeful that when it breaks in, something even greater will happen. I am already quite pleased with the Sussurro. I have no idea what part is the Sussurro engine and what part is the ES.  As I understand it, the Sussurro extends the low mass concept design even further than the MIMC. 

I can only imagine that the Hyperion would be even better. 

@dodgealum Continuing to hear amazing things with this cartridge. I'm appreciating that the Sussurro doesnt call attention to itself just lets you here new things in familiar recordings and really get the musical message. My evaluation is somewhat complicated by a new phono preamp, the Pass XP-27, which is also adding to the enjoyment. I think I still have some hours to go before the Sussurro reveals its mature self.