The biggest advantage of electric massage tables is that you can adjust the height of the table during the session to suit your height, body mechanics, and technique.
Electric tables are also stronger and sturdier than portable massage tables and can support more weight. Because you can lower these tables, they are useful for clients who have trouble getting onto and off of a taller table.
Disavantages
The disadvantages of electric tables are their weight, which makes them hard to move, and their higher price. Plus, they are mechanical devices with motors that can break down, requiring repair. So, make sure the table comes with a good warranty and a UL (Underwriter's Lab) approved motor.
Features
Most models have foot pedal controls that operate an electrically powered hydraulic lift to smoothly and quietly raise or lower the table. Some models also have a non-electric pneumatic-assisted lifting system.
Some electric tables are flat while others, often used in spas, have adjustable sections. You also have some of the same considerations that you have with a portable massage table:
Choose a type of foam that's durable.
Choose a table width that best fits you and the type of massage you offer.
Understand the manufacturer's warranty and what it covers.
Other Considerations
If the electric table you buy is ADA (American Disability Act) compliant for safe wheelchair transfers, you may be able to take a tax credit.
You may be able to find discount electric massage tables on eBay: