I believe there are a few folks here who are sold on the merits of PL Premium construction adhesive...
I'm still planning my faux teak deck, have decided to bond it to the epoxy glassed subdeck using weights while the adhesive cures, but can't decided between these two adhesive compounds.
I've compared the technical data sheets for both... and to the best of my ability to discern, it looks like they're basically the SAME stuff, polyurethane, moisture cured, similar temperature ranges, viscosities, densities, elasticity, etc.... highly comparable specs on both.
The big difference: PL is available in Home Depot and Lowes' for under $4/tube, whereas Sikaflex 291 is strictly a chandlery item, at $10 or more per tube.
I don't like to pinch pennies on materials, but I also don't want to run out in the middle.... and don't want to have to buy WAY too much of the expensive stuff to insure I don't run out. If I use PL, more can be bought at a place just 10 minutes away... better than 40 minutes away, or via mail-order.