Vim-$\rm \LaTeX$'s \lv command with Sumatra PDF

Why do I switch my PDF viewer?

• Ado* Read* is proprietary. (EULA)
• Sumatra PDF is free. (GPLv3)

Go for FLOSS! Go for freedom!

Actual process

Original settings for Ado* Read*: let g:Tex_ViewRuleComplete_dvi='C:/.../AcroRd32' in _vimrc (No extension name)
Problem: How to change Vim-$\rm \LaTeX$'s setting of \lv?
Trial 1: Set g:Tex_ViewRuleComplete_dvi='C:/.../SumatraPDF' in _vimrc (No effect)
Trial 2: Set g:Tex_ViewRule_dvi='C:/.../SumatraPDF' and disable g:Tex_ViewRuleComplete_dvi in _vimrc (No effect)
Trial 3: Set g:Tex_ViewRule_pdf='C:/.../SumatraPDF' and keep g:Tex_ViewRuleComplete_dvi='C:/.../AcroRd32' in _vimrc (Ado* Read* launched instead)
...
Trial n: Set g:Tex_ViewRule_pdf='C:/.../SumatraPDF' and disable g:Tex_ViewRuleComplete_dvi='C:/.../AcroRd32' in _vimrc (No effect)
Solution:

1. Change PATH environment variable. (You can change it for vim runtime and keep the original one in other programs. See my newer post for details.)
2. Set g:Tex_ViewRule_pdf='SumatraPDF'
3. Disable g:Tex_ViewRuleComplete_dvi in _vimrc