vinny..yes the try all is a super light weight bb ......not to strong mind but deffo light.... id always say isis over st....as some one has already said the bb spindle has more contact with the crank arm witch offers a stiffer feeling drive terrain...... and i think you will find more isis trials specific crank arms than thear is square tapperd my cranks of choice are the try all cranks....super light weight yet really strong and stiff....although the deng crank arms are pretty strong to and most of the street riders go with those. ISIS bb....id recomend a ko bikes isis bb.....dammmmmmm strong and has decent bearings that run really smooth .cant go wrong with a ko bikes bb dave x