Tantalum electrolytic capacitors are made for both through-hole and surface mounting, and are generally small and light, requiring no mechanical support. Aluminium electrolytics, on the other hand, are relatively heavy, with a centre of gravity some way from the board. Wire-ended types will probably need some support with a silicone gasket, depending on the vibration requirements for the end product. Large aluminium electrolytic capacitors need to be separately mounted, and are generally not placed directly on a PCB. Where they are, they need hand mounting and soldering, with ties or screws used to secure the body.
Aluminium electrolytic capacitors are usually in good supply: in times of high demand, deliveries in tantalum capacitors can extend substantially, tantalum being a relatively scarce resource.
All electrolytic capacitors need care when assembling and testing, to ensure that they are correctly connected – they will literally ‘blow up in your face’ if the supply is reversed. If you are using large electrolytic capacitors, then test equipment should be shielded from the operator in case of capacitor failure.
The electrolyte in aluminium electrolytic capacitors also tends to dry out, with the result that very old stocks of parts should not be used.