Want to change a small part of character mesh. Is Dynamic Topology appropriate?

I have a character mesh all set up but would like to change a small part of the mesh by sculpting. [Proportional editing not suitable.]
I am aware multires to 3 levels subdivides the whole mesh and slows the computer badly.
But I understand that Dynamic Topology can be applied to a local part of the mesh.
But clicking dyntopo brings out a warning about vertex data and that existing modifiers will lead to high poly on return to Object mode.
So kindly advise how to proceed.

It depends on what you want to change and what you want to do with the final result.
Note that as the warning tells you, you will be losing vertex data which also includes and UVs you have assigned to your mesh

The warning shows up because it will be graphics intensive (just like Mirror Modifier/Subdivision Surface etc.), but like Richard Markley told you, you will lose your vertex data.
If you just want to smooth something or pull it a bit, I won´t use Dyntopo, but if you add something with high detail (like sculpting an ear cup) I recommend using it!

Thank you, Richard & NGCHunter, for your remarks.
My character already has a Mirror & SubSurf mods. So I will have to proceed with caution.

you could retopo another objet above your existing object!

happy bl