I enjoyed working on this project quite a bit. The directions are more challenging to follow/less detailed than typical "LEGO" brand but if you've built other block creations before, you can probably figure this one out. I did notice towards the end the directions became even more vague and you had to look ahead towards the next step (or two) to understand what exactly you were supposed to do for the step you were currently working on.
First major difference from LEGO is that the very first instruction is to open all bags. You will need pieces from various different bags throughout the entire build so unfortunately (or fortunately if you like the challenge of finding pieces) you can't use "Bag 1 for steps 1-30, Bag 2 for steps 31-60, etc.). I used Tupperware to keep the parts somewhat sorted and quickly caught on to where I should expect to find a particular component.
Most of the 'x' sticks that need to go through the gears and wheels are VERY tight. I ended up bending a few of the sticks trying to force them through.
There were other areas where the fitment was so loose that I ended up using super glue to ensure the pieces would stay together.
Spark plug assembly was arguably the most challenging piece of the puzzle because the components simply would not fit together. I wound up drilling out some of the small light grey connectors to allow them to slide down the white cylinders.
Also, I was unable to get the pushrods to connect (they didn't seem long enough) so when I first cranked up the motor the rods moved a few other components out of the way and ultimately ended up falling off. I do not currently have them connected which is a bummer.
Overall, happy with the purchase but wish the fitment was a little more precise (I can get over the directions criticism).
