I have a Hydros SL III on a 3wt trout Spey. Used to have it on a Sage One and now on a Loomis IMX Short Spey 3wt. Have used 30lb Lazar Line as well as 30lb Catfish mono and it has been great. It seems to balance both of those rods pretty well. Every once and a while you’ll get a loop of mono between the spool and cage, but not often. The SL is smooth and has plenty of drag for any trout out there. I recently put the SL IV on the Loomis 5wt short spey and that balances well too- the diameter is BIG, which does help with memory on the mono.