Jaka speaks English as a second language and I think he sometimes comes off as being rude when he doesn't mean to. Cut the guy a break because he is trying to help you. He's not always right, but he is always trying to help.

There is a grain of truth in what he said though. You will beat up this airplane. You may not auger it into the ground (probably won't actually if you work with an instructor and build your skills progressively) but you will have the occasional bit of damage. I've always said a trainer doesn't even look right until it has 6-7 patches in the covering and a main gear that's bent six ways from Sunday but somehow still rolls straight. So enjoy the building process and make it the way you want to make it, but also understand that it's not going to stay pretty forever.