Thanks for the responses.
I was pretty sure i knew that the splits were better, less turbulence etc. Just wanted to know if anyone noticed this on our applications. At a guess, most people wouldnt venture far past 250rwkw.
Just weighing it up, its going to be alot harder to weld up a pipe with a split in it
Thing is with the pipes you can buy, they are 300ish and upwards of that for split. That is just way to pricey for a bit of steel.