I am swapping out my benzalkonium chloride wipes in the first aid kit for chlorhexidine wipes. Chlorhexidine gives a more persistent disinfection (whoops - antisepsis) that would be beneficial in preventing infection. Asfried1 is right on how tap water is usually adequate for irrigation, but if my FAK had to be used in a non-urban, or a setting without the comforts of home (and hygiene), then persistent activity against microbials would be useful since you can't count on 1) a clean environment, 2) your barrier dressing holding up.
J Hosp Infect 1984 showed that chlorhexidine prevented non-infected wounds from becoming infected, better than saline - this is useful in non-urban settings.

Regarding the miox, also electrolysed oxidized water was shown to be markedly superior to water or saline in serious wounds such as burns. It was superior in preventing local and systemic infection. I have no idea how the miox unit would convert in terms of getting the right concentration, but I remember I investigated this a while back and the marketing rep had told me a solution of 2.5% was made (standardized to chlorine though, and it didn't take into account the other more potent oxidants that miox generates).

Eric