I have 32 boa boots with two boas per boot. Had them for at least 5 seasons now, 20-30 days a season. I use them for touring and resort. I'm generally really impressed with the boa system. I don't have boots designed for touring so I like that the boa allows me to loosen the boots quickly for uphill and tighten them quickly for downhill.
All that to say, today when I pulled on the boa to loosen it, the fabric tore and the boa is now just held on by the cables. It still works but I need two hands to operate it. I may try some shoe goo because otherwise the boots seem to be going strong.