It seems to me that each game type/format has a different set of requirements to be the best. Seems to me that the tourney path is somewhat softer, though there are more hurdles to jump.
Tourney's also offer a more controllable set of losses. But if you're hot shit on the felt, you can earn a regular hourly income from playing cash tables. Whilst I play cash games occasionally (e.g. to obtain a 'throwable"), the swings can be great and the field aggressive.
At the end of the day, I have two "moods" for playing. One mood is laser-beam focussed with the view of finishing people off as viciously and quickly as possible (so turbo and hyper-turbo games are preferable), whereas there are other times where I just want to "play poker". In such instances, I prefer the slower pace of a regular speed tourney (e.g. with 10m blinds).
The phrase "you cannot win a tourney in the first half hour" applies here. Patience. Discipline. Aggression.
But if you are looking to replace your salary with income rom poker, I think you've got a better opportunity (at least in the early days) of doing that from cash games.
Cheers,
ObbleeXY