How to spot a good King Palm to buy?

[BayAndroid]

Curious to know if you guys have pictures of good specimens that you purchased and maybe pics of what they looked like at the time you bought them. 
I purchased some kings from Home Depot a couple years ago, doing it again, I might have chosen some different plants had I known better. If you have no pictures, just describe what you'd look for. I'm thinking about adding some Alexandrae to plant in my front yard at some point soon. 

 

[Ben in Norcal]

What I have learned is to always buy 5-15 gallon size.  Plants I put in at 5 gallon size are the same year, are bigger than box plants within 3-4 years.  These things get set back if they are in boxes too long.  They are rocket ships, so but small, keep as wet as possible, and stand back.

 

[BigWaveDav3]

I purchased quite a few almost 2 years ago in 15 gallon size that were triples and singles. The ones that were most hearty in the crown size when purchased are what has grown the most. Even with the multi's, some had twin size pairs of trunk, with a smaller third. They have grown relative to their initial size. I'd look among the bunch for the ones with the crowns with the most mass and healthy looking.  (Ignore some browning/cosmetic issues on the outer growth facing the major sun exposure - in my locale the south facing side)

[Gonzer]

If it has a shiny crown.

[chad2468emr]

Hearty, robust, green, and perky. Ignore the ones that are overly saggy and pay attention to signs of pests like chewed leaves, spotty yellowing, and spider mite webs. Avoid ones with signs of nutritional deficiencies like necrotic leaflet tips on newer leaves, even yellowing, etc. For the most part, look for the same things you would for any palm. Don’t worry too much about damage that is simply cosmetic because these things grow so fast that you’ll be able to cut off anything ugly in a few months. Mine put out 2 fronds a month at their fastest. 

[BayAndroid]

Thanks for all the great responses. I like how they were all unique, I'll take this with me on my next shopping trip.