Depends what you're doing, honestly. Some software won't tolerate running off a network mount at all for various reasons, if so you're sunk.
Some is just slow because it's inefficient. It's been a while since I had to resort to this, but accessing a big svn checkout over cifs is so slow as to be useless.
Some is just slow because it's inefficient. It's been a while since I had to resort to this, but accessing a big svn checkout over cifs is so slow as to be useless.