I loved Three Musketeers. Somehow Dumas' discursive, humorous style just really resonated with me ("He thought he saw the barrel of a musket glitter from behind a hedge. D'Artagnan had a quick eye and a prompt understanding. He comprehended that the musket had not come there of itself, and that he who bore it had not concealed himself behind a hedge with any friendly intentions.")
I find I like Three Musketeers in a similar way to how I like Name of the Rose or Cryptonomicon: they have the same approach of spelling things out in humorous excessively detail, but Three Musketeers spells out obvious things, and Cryptonomicon spells things out using unnecessary mathematical analogies. However, I know other people don't subscribe to those similarities.
It naturally has the problem that you can't write a more serious book in that abstracted style -- the beginning of Count of Monte-Cristo bothered me for that reason. It feels silly to say "and he proposed a conspiracy and the others agree" or "he fought vigorously and prevailed", and you want to object it couldn't happen, whereas in Three Musketeers it makes sense. You generally need to impute the text to a fictional author, treating it as a bit legendary, and then it works.
Brust avoids the trap of following the original too closely; many incidents are reflected in spirit but not detail. If you like either Three Musketeers, or the Taltos books, I think this is very worth reading. (As is typical for books described, it is available to borrow :))