For me unsound is asking the question "is it seriously worse than alternatives" and I feel yes it is. Specifically worse than playing any regular opening. e4 e5, caro, sicilian of almost any kind, french and more.
Id honestly play the Alekhine/Pirc/Modern/Scandi/Evans gambit (as white) way before I would play the Latvian. So for me there are many many many choices better than the Latvian objectively and practically. At some level though it shouldn't matter if it is sound or unsound. But I assume most people are slightly above that level where they should infact play something even remotely sensible.
Am I going to suffer with the Latvian most likely. I suppose your play style also takes some effect in it as well. I am more of a solid/small advantage/positional/grinder player than a wild Tal sacrificer. So the opening does not really fit my likes.
Marshall is very sound in the Ruy and leads to a quick mate if white does not defend properly. I recommend it to anyone for sure (willing to put in some hours to study it deeply enough.)
Id honestly play the Alekhine/Pirc/Modern/Scandi/Evans gambit (as white) way before I would play the Latvian. So for me there are many many many choices better than the Latvian objectively and practically. At some level though it shouldn't matter if it is sound or unsound. But I assume most people are slightly above that level where they should infact play something even remotely sensible.
Am I going to suffer with the Latvian most likely. I suppose your play style also takes some effect in it as well. I am more of a solid/small advantage/positional/grinder player than a wild Tal sacrificer. So the opening does not really fit my likes.
Marshall is very sound in the Ruy and leads to a quick mate if white does not defend properly. I recommend it to anyone for sure (willing to put in some hours to study it deeply enough.)