By "wired" I think you mean connected by a hose (no wires involved). The dive computer is either attached to the air hose or it is wireless (for example by bluetooth). Both are reliable. The biggest difference is cost. Computers attached directly to an air hose are significantly less expensive. Those with a sensor that screws into a HP port on your first stage are more expensive.
Personally I am looking forward to less expensive wireless units with the ability to see your buddy's remaining air. They are available but costly.