Delta vs. Cartesian
There's absolutely no practical difference in speed as both types of printer can move the print head vastly faster than you can feed filament through a nozzle.
Deltas have a round bed, can easily be made tall and generally take up less room for a given print area. This means they work well for people making tall, round objects, such as statuettes. It's hard to make full use of the print area for square objects so the practical benefit of a bigger print area in a smaller space may doesn't always work out.
Cartesian printers have a rectangular build area, optimised for boxy things. The tend not to be as tall.
Obviously if you don't intend to do prints to the size limit of your printer, it doesn't matter which you have.
Me, I print right up to the edges and I'm considering building a bigger, cartesian, printer as the ability to print sizeable rectangular enclosures would be useful to me.