"If you want to play with Tuners,the 23" is a better arrangement,as the increase in lengths grants more to tune. I've done lots of both and will always take the shortened spouts' rigidity and laugh a Whiners crying about "chokes".
For the sake of saying so, the 18" is threaded for "chokes" but the 23" is crowned from what I can gather. The 23" HB definitely has a match chamber but 18" sporter's description sadly is a little unclear.
However, I'm leaning towards the longer barrel.
