I like everything about Lego Technic's except their price. I sent them blueprints on a flat side double pine 4, 6 and 8 pine block that would allow symetric building in more than a ground up dimension, but they replied they did not take suggestions from people. I asked for nothing, and got nothing. I am surprised someone has not done this yet. I have 3 large bureau drawers full of every lego piece you could imagine. Lots of linked tracks, and very to find hard parts. I purchased garbage bags full of Lego pieces at Tag Sales from people who were literally selling 100's of dollars worth of Legos for $5 bucks by the garbage bag, full to the brim. By the time my son was two, I had his future of Legos secured, and only purchased hard to find pieces from that point on, paying never more than a dollar a bag. He's 19 now, and all those Legos, many of the pieces discontinued, are like new. Incidentally, plastic model glues allows you to make permanent models, just be sure you think it out, and dry fit carefully, because you will never get them apart.