So long as you're not going to be trailer launching, the Dexters will probably be fine. I tried those for a few years on my trailer when I first built it, and they rusted something terrible. . . . But I was launching in salt water
repeatedly, which eventually led me to those galvanized Eliminators.
I don't think the Dexters have a replaceable spindle, but that's not a deal-breaker. Just be careful not to, say, misjudge a corner and get one wheel
stuck up on a curb where it bears all the weight of one side of the trailer. That can bend a spindle. . . . Ask me how I know.