Hana SL or ML?

You’re all missing the key point.
The main difference between SL and ML is the stylus profile:

SL - Shibata
ML - MicroLine

MicroLine profile is better and life span of this profile is longer.

When you’re buying Moving Coil cartridge it is very important how long you can use it, it depends primarily on the stylus profile. Always buy an MC with the most advanced stylus profile like MicroLine, MicroRidge, Gyger, Replicant 100 ... etc

When your MC cartridge is worn, even if it was relatively cheap cartridge like Hana, you will pay at least half of the retail price again just for retip, even more if you will change the cantilever from aluminum to a better one.

Anyone can explain in details what Hana will do for you when your cartridge is worn? Can you ship it back for re-tip to Hana (aka Excel Sound) or they will replace your worn cartridge with a new one ? What is the price ?

Because when you will re-tip it with something else you will get different sound.

I really liked the SL but the ML improves everything the SL does well and makes it better. More refined, better detail, separation, and frequency extremes. Bass was clearly better.

Exactly! This is what a refined stylus tip can make, Micro Line stylus is better and much more complicated than Shibata, so the improvement is obvious with any cartridge (MC or MM/MI).

@mekong56 Can you explain their policy regarding upgrade? What do they charge when Hana is worn and a customer willing to send it back for repair or upgrade with another model ? Do you know ? 

@mekong56 

 I was given a $300 or $350 credit towards the M when I traded up from the S. I thought that was pretty good, and I don't particularly like buying or selling used cartridges.

Yes, that's very good, thanks