I just finished my 18SS. and it looks amazing, changed most of my stock parts to alumiunum and added a roll cage, you'll have fun building it I know I did. Can not wait to start driving it.

So to answer your questions

Very easy to build
The stock part are durable but it doesn't hurt to upgrade to a few aftermarket parts.
It needs about 20% nito fuel
and I believe it runs a top speed of 75 kmph.

Feel free to pm me if you have anymore questions and keep an eye open when I post my pics once I finished painting my body.