I do not have a lot of experience in the market of trailers but I do own one. I have a small 2 hole Premier Aluminum trailer (out oif Tulsa, OK) I bought second hand. I have had it for a year ( it was about 5 years old when I bought it).
Aside from not having built in exhaust fans I love it. I have small battery powered fans on the top front holes to exhaust air. Temps inside stay reasonably mild even in summer ( I do have a themometer in one of the holes to check it).
Quality has been good and no problems with it at all (leaks, axel, etc...) Its also light enought o manuver by hand and fits in the 3rd car garage.