Don't worry about the folding tongue modification--it was a result of bad roads of the South…I 5 would not have anything like that! :sad The trailer was undersized by some criteria--but had over 10,000 miles on it before the failure. No rust or corrosion found.
A dual axle trailer will do will, and I have towed other C Dorys over nearly 20,000 miles over the last 11 years with no issues. The "new" trailer under the boat is much more substantial.
I would ride in both boats, under the same conditions. Both are quality boats, and you cannot go wrong with either. I seem to hear of more who go from Arima to C Dory than Visa Versa.