What do you folks think of aluminum sided trailers?

Both have advantages and disadvantages.

Second opinion

Aluminum PRO's

Cheaper-more trailer per $$$.
Easier and cheaper to repair if you have water issues behind a side wall.
Heavier to tow with wood framing construction vs. aluminum in most laminated trailers.
No Delamination
Don't fade as bad over long haul. Painted surface.

Aluminum CON's

Harder to clean and maintain caulking with all the ridges in the aluminum.
Not as "Clean" a look/attractiveness (Subjective).
Dent's/Hail damage.
Fiberglass insulation in Aluminum trailers not as effective as block foam which is often used in fiberglass trailers for cold weather camping.

I've known a lot of people that have owned both and were happy with their choice.