Here are some photos of two canvas prints of the same size and same illustration.
The biggest difference is how the canvas is mounted. With mine, I use wood stretcher bars which leaves the canvas exposed from the back. The canvas also has a slight "bounce", if you were to drop a penny on it. The outsourced canvas glues the canvas directly to a composite board, resulting in a very hard surface. Both have their advantages and disadvantages. The wood stretcher bars may warp in extreme temperatures (I've personally never had complaints or heard of any extreme damage), while the glued canvas uses glue...and you pretty much can't salvage the actual canvas to re-strech if needed. But the harder surface can also be very appealing.
Side by side comparison of the two canvas prints.
Left - Mine
Right - Outsourced
Just the outsourced Canvas - The sealant/canvas combination they use certainly has a more reflective surface.
My canvas is much softer, and the threads are slightly finer. The protective sealant I use is also specifically made for this canvas, by the same company.
Closeup of edges and corners. Both are gallery wrapped, mine are .75" thick, and the outsourced canvas is about 1.25" thick. Their corners don't have little bulges like mine, since they are machine wrapped and glued, while I used hand tools to stretch.
Closeup of my canvas. Hard to capture in a photo, but the line work is much more fine and less muddled.
Closeup of outsourced canvas - colors are 100% accurate, but some of the linework becomes muddled because of the materials used.
Back of my canvas. The canvas is stapled to wood stretchers, with hanging hardware screwed into the bars. Rubber standoffs in each corner.
Back of outsourced canvas. Cleaner looking of course, the black board is glued on, and the hanging hardware is glued onto the blackboard. My biggest concern here, while it looks nice, is that glue is used and that seal may weaken over time. Hanging hardware is also not directly attached to the canvas board.