Generally, ball bearings are less expensive than roller bearings for small bores and light loads, whereas roller bearings are less expensive in the larger sizes and heavier loads. Roller bearings are more resistant than ball bearings to shock or impact loads, but lack some of their speed or misalignment capability.
Probable misalignments between housings and shafts suggest self-aligning bearings are needed. At least make sure the bearing can stand up to expected misalignments.
Ball thrust bearings should be subjected to only pure thrust loads. At high speeds, a deep-groove or angular-contact ball bearing is usually a better choice -- even for pure thrust loads.
Ball bearings and cylindrical roller bearings have low friction coefficients.
Many different bearings are available with built-in seals for prelubrication. Some are lubed for life. Give special consideration to these types in consumer applications and applications where maintenance may be marginal.