According to Aaron Fude :

I can't quite figure out the advantage of low-voltage recessed
lighting over the line voltage variety. I *have* noticed that they are
more expensive and that dimmers for them are much more expensive. But
what the advantages to consider?

I'm not altogether sure of them myself, however, they do have
the advantage that if you're doing large and complex systems
with common transformers, they are cheaper, and since you don't
have to follow the same rules for 120V for 12V, a lot less
trouble to install.
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.