Although this is a complex model, the building instructions are fairly simple. In my opinion it should have been a bit more difficult, adding more parts per step.
There are in total 6 instruction books included, all of them are for the A model.
It will take you approximately 10 hours to build it.

When you're finished building, you'll see a massive vehicle in front of you, very rewarding after many hours building. It really is an impressive machine!
As a comparison, see the picture below, my 42009 in front of some other yellow technic sets.

Time to test its functions!
This model includes only one PF L-motor, but it drives multiple functions.
    - Outriggers horizontal
    - Outriggers vertical
    - Lifting the boom arm
    - Extending the boom arm
    - And of course Lowering and raising the hook
There are also some manual functions:
    - Steering, is done by a Hand Of God wheel at the back.The varying wheel angles for 8 of the wheels are               making turning smooth and easy.
    - 360° rotation of the upper half of the crane, even when the motor is on.
    - A working fake engine when you drive the crane

It's good to see so many functions, but but not all of them work properly, there is room for improvement.

Cons
I think the motor should have been a bit stronger, maybe an XL motor had been a better choice for this model?
Movements are all quite slow. Perhaps this is done intentionally, in order to develop more torque.
The outrigger system is quite nice, but sadly isn't strong enough to lift the vehicle.
I was expecting the boom more extendable and a bit stronger.

So, there are some negative points, but do not let them scare you off.

Pros
It is a great looking model, with lot's of functions.
Offers a lot of building fun, plenty of interesting mechanisms.
There is also a good looking B model, but i haven't builded it yet.
A lot of pieces, ideal to start your technic collection.
Great value for money.

    The B model, also an attractive model.

Our first new Lego purchases after the dark ages were the 9390 Mini Tow Truck and 8065 Mini Container Truck.
They are some of the smallest Technic sets you can buy. Ideal to rediscovering the joys of building Lego sets.
The thing that struck right away is that Lego Technic is studless now! A big change!!

First the 9390 Mini Tow Truck:
Pros
This must be the miniature version of set 8110 Mercedes-Benz Unimog. (fantastic flagship set)
It offers 2 functions, for a mini set that's really good. The front wheels steer and the crane hook raises and lowers.
Good price

Cons
Nothing really worth mentioning

8065 Mini Container Truck
Pros
A very clever design and one that is really entertaining for its simplicity and effectiveness.
Loading and unloading the bucket is done by a realistic and precise mechanism.
Good price

Cons
A second function would have been nice, but probably difficult to add in this compact model.
As a part, the bucket is not very useful to implement in MOC's.