The question: compared to a 50mm 1.8 not much bulkier (size / weight) worth what?
=> Quieter, better than the 50mm from 2.8 to 2.8 and on 5D, 10mm less possible to fit wider and lower the minimum speed to shoot 1/15. If you want F2 50mm otherwise it mandatory 40mm wide best (. True auto-focus, better construction Etc ...)
Compared to other optical, considering the price and the quality provided is the goal to have in his pocket. Turns your 5D lighter than urban Machine Fuji X100 (which it has an opening of 35mm F2 but on APS-C). Ideal for holidays, outings or like me, all coming all the time. Replaced 50mm 1.4 for me too fragile and too slow a 35mm 1.4 but not very close but different in daily use.
For the weather resistance will have to wait. But it seems sturdy and saw the embedded glass it would be a shame to see it fall in the harbor (but you never know ...)
