With Skinny you can make Sets for all the body parts and area you want the paint individual.
That way you wouldn't affect other areas by mistake. As you know Maya have "normalize weight"
feature that change skin value special while using the brush Smooth.

Please email me on any bugs you find with this version, or good idea for Skinny

Update on v3.8
- User can paint on selected vertex's ( isolate mode )
- Copy one Vertex weight to other ( solve crazy vertex's problem, and matching weight between different mesh's )

After Sourcing, run command: AS_Skinny;

More Features
-Smaller and faster Paint weight UI then Maya's
-Rotating Joints while skinning. Excellent feature for seen the skin in action without leaving
the skinning process.
-List Joints by: Aphabetical, By Hold , Graph order.
-Hold Joints & influence by: Selected or All
-"Remove Influence", just select the joint and remove.
-"Zero Weight", show joints with zero weight.
-"Create Fullset", create set from SkinCluster members.
- "MeshSmooth" to see the model hi-rez while skinning.
- "Skinny Active" to active skinning mode and quick exit this mode.
-"Save/Load Sets" to file

http://www.reel.asimation.com

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