There is no "best of VBR Old and New", you can only use one or the other. "Default" will default to VBR Old.
--alt preset standard regularly uses q=3, as you can see in the DOS window if you call this preset via the external encoder option. However, Lame may override your q=5 and use the default setting q=3 anyway because --preset settings usually override user defined settings, but it depends how the settings are communicated to the lame.dll, which you never really know when using a frontend.