I worked smalls in a few buildings. One was in a secondary "upstairs". Man, it gets extremely hot with little ventilation during summers. Also, there are some physical jobs such as de-bagger (which can be not-so-nice on your back, twisting and turning a lot.)
Overall, two of the easiest jobs are ODC international clerk as well as haz-mat auditor. Those two are cake, and I would pass on the small-sort 100% of the time. Small sort is hell in a playpen in comparison.