Purity: Cobi COB1621 Construction Bulldozer Review

I picked these sets up at the Hobby Bunker way back in February of 2018.

Box.  Original price was $18.99 for a $0.17 Price per Piece.  I paid
$6.00 for this at Hobby Bunker.  This yields a $0.05 Price per Piece.

Instructions.

This was stamped inside the box.  I'm not
sure what it is, perhaps a mark of authenticity?

Minifig.

Parts 1.  Tires, Plates, and Tiles.

Parts 2.  Rims, Plates, Tiles w/Studs,
Bar Plates, and Round Plates.

Parts 3.  Plates, Brackets, Brick, Wedge Plates,
Corner Plates, Double Sided Plates, Levers &
Bases, Large Cheese Slopes, Open Truncated
Cones, Bars w/Angle, and Axle Tiles w/Studs.

Parts 4.  Tiles w/Studs, Plates, Textured
Engine Block, Hollow Slope, Jumpers,
Round Plate, Cheese Slopes, Studless
Slopes, Brick, and Pino Joiner w/Clip.

Build.  Battle Cart (2Ra+d8 (cannons) 2B (smoke canisters)).

The Questions:

Can you build something -- a frame, station, or starship -- right away?  Yes.  (+5)
Is it below, at, or above the golden ratio?  Above.  (-10)  (The Golden Ratio is $0.10 per part.)
If you can't build a frame right away, or choose not to, does it have parts you should be able to put into use right away?  Yes.  (+5)
Does it have more than a handful of immediately useful parts?  Yes.  (+5)
Score: +5 (B+).  I may have to track down more of these, it has some useful parts.