At home I tend to use the torque wrench once in a while, but not always. It helps get a feel for how much force you need to put on the nut to get it tight enough.
For 105Nm do not tighten it as hard as you can, it will be way overtightened. The only bike I ever had too use a decent amount of force to tighten the rear wheel nut was a TDM900 which for some reason required 150Nm.

You can train yourself to get a feel for it. Try it a couple of times with a torque wrench, then try it with a regular wrench/ratchet and check with the torque wrench.

It is better to have it a little looser than spec than tighter. You'd have to be way too loose before it becomes a problem, but it can be pretty easy to strip threads if you go too tight.