What is a better option, wired or wireless cameras?

There are advantages and disadvantages for both. Wired cameras provide superior connection and never go flat, they also have a higher cost for initial setup when cables need to be run to each camera. Wireless cameras mostly operate with batteries and generally cost less overall as you do not need to run cables for them.. You will find yourself having to get them down and re-charge them and as life goes on the battery life will decrease. Wireless coverage could also be an issue in locations where you ISP modem just will not reach with its single-band wifi or constantly drops out.