I recently had major problems with stringing on prints with all materials. Using defaults settings, cleaning the hotend and rebuilding did NOTHING to help.
I bought a new hotend and heater/thermocouple and assembled them in the following manner;
First off I bought some high (350 degrees ~C) temperature thermal paste, and some aluminium powder (used in flash powder).
I mixed the Al powder with some of the heat paste and applied this to the heater and thermocouple before inserting them into the hotend block.
I applied some car exhaust sealant to the filament feed tube where it enters the hotend Al block (this stops oozing from this point when the head gets hot and expands).
I put some heat paste on the throat of the hotend tube where the finned heatsink with the fan attaches (to help keep the heat break cooler).
I reassembled the whole print-head and printed a test piece.
The result was NO STRINGING, the extruder heated up a LOT faster than before and the print quality is now as good as a moulded part (IMHO)!!
Layer adhesion is greatly increased and overall strength of the print seems around twice what it was before.
Hope this helps someone.
Zsuite STILL need a retraction setting that the user can define as some problems simply cannot be cured with this mod.