I have a single ax trailer, I’ve had no issues. Pro’s on con’s to each, single ax is a little easier to move around but tandem gives a little more piece of mind. I bought mine used, previous owner had owned both versions and insisted with the 115 you do not need a tandem ax trailer, with a 150, yes get the tandem but that would only be the 09 model. I’d rather of had a tandem but like I said I’ve had no issues with my single ax trailer.