Had mine in us for 2 years. No leaks around the edges and barb placement has never been a problem. This is my first loop.
If I were to make any changes it would be the plug and plug area. The plastic plug is very shallow meaning you don't have very far to tighten before you bottom out. Over tighten and you could have problems. I use a US Quarter to open/close it. To specifically address the air-trap there, there is a ring of acrylic that holds the plug and hangs down into the res. This area should be redesigned, perhaps have that lowered section extend all the way to the walls - the gap there is probably 3/16 of an inch or less.
I like the trickling water sound and the bubbles swirling around. Its like some counter-top decorative fountain. I left the loop sealed for over a year and only a few bubbles have formed.