Rendr Sketchbook

Because I have been practicing capturing likenesses, I decided that I wanted a sketchbook for that alone.  I've also been using wet mediums much more, so I needed a sketchbook that would allow for that.  Wandering through my local art supply store, I found this Rendr sketchbook, which claims to have no show-through pages.

We all know that traditional sketchbooks cannot begin to claim that.  Rendr achieves it!

Here's the sketch I did of Kelly MacDonald in gouache.  The pages curl, but that can be remedied by just closing the book for a while.  But does the paint show through? 

No.  Not at all!  I'm impressed! 

What other sketchbooks would you recommend for this type of work?  Do you keep sketchbooks for separate subjects?