Yes the plugin is quite slow . you can save your basic meshes  as a tool just after the PoserImport  , when you load it as a tool it's almost instantly .

With complex clothing I had some troubles , parts of the mesh are missing with PoserScaler.

I use PoserScaler because it's all inside Zbrush and  because   I couldn't work with ObjScaler - it is a problem with my French keyboard I think .

For V4 it's the only way I found to have no displacement . I work on clothing and most of the time direct import/export works correctly .

Alice's and GND4's Tailor !
Check my free clothing fits : www.alizea3d.com