The differences I could find between the two was the Trianglelab seems to be a very slight modification to the outer case ( larger corner bezel at the top of the outer case) and the Bondtech is a very nice 3D Printed nylon sintered case where as the Trianglelab is an injection moulded casing. Both performed extremely well in my tests on both a v1, v2 and V3 prototype. The Trianglelab was was used in both Direct drive and Bowden configurations. All tests yielded identical results regardless of manufacturer. Take your pick. If you’d like to support the original designer, go the Bondtech. If you, like me want to dip your toe in before investing in the Bondtech, the Trianglelab performs extremely well and arguably has a slightly better overall finish (they’re both very good) due to the manufacturing process employed.
Oh the trianglelab also came with the parts to mount the extruder upside down. The Bondtech did not.