Pretty good, needs improvements.
There are some great things you added to this genre of "deliver goods from point A to point B with physics." The upgrade system is nice and actually makes you feel like you are working towards something. The bonus pieces are a good addition too. Some are useful, others are just for looks it seems. But it makes it interesting to try to get the bonus pieces to see what it is. I think an improvement with that system is maybe a way to choose what you want after you have it. At least with the useful items. Such as a choice in outfit or helmet.
Some improvements though:
You NEED to fix the crane in a later version. I liked the idea of the crane, where you could control when it went down and all that (also the ability to control the environment was cool too). BUT, the crane caused more problems then what it solved. Many times it would have a very difficult time picking up things that were not perfectly aligned in the cart (as it is in most cases since it gets shifted around during transit). Also the crane would push things on the cart as it would reset itself. The arm would spin around and there would not be enough clearance and it would collide with the cargo as it was trying to go back to it's home position to try to grab again. I think to fix that it needs to be higher up and drop down further, or the reset animation should be different to not need it to go all the way around. The crane was extremely frustrating because at best it would just take a lot of attempts to grab the cargo (causing the bonus clock to run out). and at worst it would push the cargo off the trolly (at one point it even grabbed the cargo, and when it threw it to land on the conveyor belt the cargo didn't make it to the conveyor belt after being thrown and i lost that cargo).
I had similar problems (though not AS bad as the crane) with the suction pipe. sometimes it would pull things up, but they wouldn't go into the pipe (it would miss, or get stuck on the side of the pipe), and then it would turn off, and it would drop down and i would lose that cargo which was frustrating because I feel that after i get passed the level I shouldn't be losing cargo due to the function of the item collectors failing. Though I do want to say that I enjoyed the idea of the item collectors, instead of a "get to the end and it is done." It makes it feel more like a shipment. It just needs improvement.
The other problem I had was with the coin dispenser that would give out the coins after the cargo goes into it. It needs to have a manual activation because while i was busy trying to get cargo picked up, it would dispense coins all over the place and some of them i would lose, or in an effort to get to them in time I would lose precariously balanced cargo that fell off as I moved. One time i also had a problem where I delivered so much cargo at once that the glass window in the cargo dispenser filled up, and the game had a glitch where the coins appeared ABOVE the dispenser (since there was so many). And when it dumped the coins, the ones on top of the dispenser stayed there and I lost them.
The game WAS pretty hard too. And for the amount of time it took to go through it, I didn't feel like there was enough rewards (not THAT many upgrades, etc). There also needed more explanation as to what different upgrades did. I would suggest more performance upgrades that could be switched back and forth to be better in different situations (kinda like how the upgrades in the game "Trolleez" works). I think a combination of fortifying your cart, as well as changing performance upgrades, would make the length of the game better.
Overall I really liked the game. It really improves the genre of delivering goods physics games. I think with improvements the next one will be great. The difficulty WAS pretty tough, even with upgrades. If you can improve on those things, the next one will be so much better. Overall good game. Just required a lot of time and patience to get through it all, which might have lowered how many people were willing to play it for a long time.