Re: 6 MT (baxteR)
If you are talking about the actual shifting, i.e. the gear change event, it should be very smooth. WHEN, and note it is a capital when, the cables are adjusted properly, it is one of the smoothest shifting cable systems I have encountered.
Certainly motor mounts are important, but if there is binding during the gear change, the engine is at it's "rest" or non torqued over position, unless you are not letting off the accelerator during a gear change. Cables are used to allow for engine movement, to prevent binding.
Clutch engagement is a very different thing, but it too is very smooth if the disc is proper and the slave cylinder is not leaking.
I would take the time to examine, if it is the gear change, that is giving you diffculty, or the clutch engagement. Get you timing right. If there is binding on the gear change, it most likely is improper cable adjustment.