Very low stocks. I live nearby, and did a season and a half on the Bognor & Petworth book, I joined Ringwood and District in 2017. So this info is a couple of years out of date. Coultershaw and Fittleworth got the most ‘pressure’ barbel-wise, although neither were ever especially busy. Coultershaw used to throw up occasional fish to decent sizes. Fittleworth catches were rarer, but it’s produced some beasts (and looks the more likely venue, in my opinion). There are two other stretches that I didn’t ever get round to visiting. You also get a couple of stretches of the Arun.
I’ve considered rejoining alongside my RDAA ticket, as I’d be able to use the stretches for early morning or short evening sessions. The price is off putting, considering the amount of waters when compared to Ringwood or Christchurch.
I spoke to experienced anglers that had been fishing the stretches for 5+ years before catching their first barbel and some that had been fishing longer and not had one. There were a few guys that would catch (I think), but it was all quite hush-hush.