I think you will find all slug pellets have either a warning on their labels to keep pellets out of water, or have a buffer zone restriction on headlands, and this includes Draza, Sluggo and Sluxx and metaldehyde so it is best to observe the 5 metre no spread zone against water courses with all slug pelletsto be safe.
Quite a useless warning as we have already noted that an application with a spinning disc is likely to throw the product much beyond the distance it is supposed to be working. Label statements saying dont put it in the water are therefore quite stupid - they know how the product is applied, and that some will get in.
Perhaps then it is the method of application that we need to be considering - 12m pnumatic fert spreaders can be bought for peanuts at farm sales and they can apply pellets with very high accuracy. 5/6m no spread areas are not enough really, although new ATV spreaders seem to have adjustable throw angles, so you can drive around the headland and just throw into the field, which seems quite handy.
Many subsoiler-type drills can be fitted with dual hoppers for well placed pelleting.
So forget the differing products, and too-narrow buffer zones, and just ban spinning disc applications.
Not for print please.