The difference between a 12v accessory outlet and a 12v cigarette outlet is as follows;
The Cigarette outlet will have a ceramic backing with a bimetallic strip in the form of a hook latch riveted to it. What this does is it heats up along with the lighter, and when it reaches a certain temp the clip lets go and the lighter pops.
The socket is designed for high heat. However, the rivet in the center is what is used to make contact with the center positive electrode of a plugged in 12v device. This means reduced contact area compared to the typical concave contact point in an accessory outlet. The reduced contact area along with possible containments should the 12v lighter have ever actually been used to light
a cigarette, causes a great increase in heat production when under high amp load.
Typically accessory outlets are a smooth metal tube with no outer perforations. This usually leads to a fiberglass sheet with a brass slug, or formed stainless connection dead center in the rear to serve as the positive connection. Unfortunately, there is no real standard of quality when it comes to 12v ports or accessories. Some 12v sockets fall
apart right away, or don't hang onto the plugs well. Others are extremely tight and have well machined and thought out parts.
As a general rule when in doubt I would assume the lighter socket can handle more amps than most of the accessory ones.
This would be if for some reason I cannot inspect the ports and wires leading to them myself. At the very least it is designed to handle heat, so even in the event that it runs hot due to load it will be less likely to melt or start a fire. My stock Geo lighter connector handled 550 watts from MI to CA and back again nearly constant. The socket was hot enough to sizzle if touched with water, but nothing failed. Under the same load my custom (high quality) accessory outlets that I added and power with 8 gauge wire from the battery were barely above ambient temp.
There is no difference between them for low powered items.
Cigarette outlets merely have provisions for handling the actual lighter, as well as resultant heat.