gadgetto

Hi all, this is my first post in this forum. I want to enter the lego technic enthusiast world and wanted to buy my first ever big model set. I am thinking to buy 42006 and 42009. The problem is, I am still not that sure to buy 42006. Is this a good set? For part donor? Actually, I just want to buy it because of the actuator and caterpillar system.