Great selection - I received this as a gift - I'm a calligrapher and enjoy pottering with watercolours so this was a bit of a challenge!
The selection of pencils and leads has covered every sketching eventuality I have encountered in the year I've had this set. From very soft 8B to relatively firm 2B graphite you can achieve wonderful shading and crisp lines.
The chalk (red and white), sepia and sanguine leads and pencils are firm and can make sharp lines but easily blend to shade.
The inclusion of some soluble graphite makes sketching skies a breeze.
The pastels are smooth to use (I've not encountered any scratchy bits) and fairly powdery - the selection of cool and warm greys, black, white and sepia allows you to mix pastel and pencil/lead work easily.
The putty eraser is easy to shape and can form a fine point. It is effective on all the graphite.
Two things would make this set perfect: a paper smudger (I don't know the proper name!) and a lead holder. Koh-i-noor make some excellent lead holders, it would be worth popping one in your basket along with this set if you don't already have one.