20 Root Canals later and I highly recommend the use of Guttaflow Bioseal in cold cure obturation cases.
Key features include it being nearly insoluble in contact with bodily fluids, great adhesion, expansion over time as opposed to previous systems shrinking and it combines GP in very fine powder form which sets over 20-30 minutes.
Available from Wright Millners Dental Suppliers and works incredibly well with single cone HyFlex EDM preparation.