If you're looking to make simple signs with more-than-decent exposure resistance? Old school is best school - cut vinyl on your final product. Even the most garbage vinyls will last many years. 3M Scotchcal and Oracal 651 are the market leaders in popularity for this application. They will outlive a printed product by lifetimes. This is how it has been done for decades. This sounds like what you need!
However, if you decide to print?? You should laminate no matter what - direct print or vinyl application.
Whether you print to aluminum or vinyl, your printer's ink longevity faces the same UV exposure resistance
.
Regardless of what Canon tells you, those inks are NOT high UV resistant, they're not even on the 3M MCS list. They are not remotely intended for outdoor competitive use.
In Las Vegas? Even the BEST inks are short life - and when you say "laminate", no laminates are considered equal in those exposures! Generic brands, PVCs, shelf garbage - none of that would survive a year. What do you normally use for those applications??
If you really are looking for LONG life for printed versions? Then you're getting into polyester and polycarbonate products with a lot of engineering behind them.