I have done my research and Jim and I both have L4's on our frag tanks. He has an l4 or and l8 on his display. We both have been running them for years. To say I'm familiar is an understatement. Most scrubbers are made from glued acrylic which can be prone to leaking and or separation from twisting. This is one of the few things that doesn't need to be tinkered with. They run like a Ferrari right out of the box hence worth the cash drop.
Turbos is not made of plexi, They are injection molded uv resistant plastic. No seams, Darn near leak proof with quality LEDs. I run a L4 on my 6' frag from its inception over 2 years ago. This one is Going on my 450. The only way you will see it for sale is if I upgrade to a L16. Which in reality I would just get the parts from bud as a L16 is 2 8's stacked. In my opinion the finest scrubbers on the market. Pricy though with long waits as said.