Does the job and looks great
Being a beginner in the mixologist profession (don't worry my skills are confined to the home) I find I have to refer to recipes and pause frequently, particularly after a couple, to remember what else you need to add to a cocktail. The great thing about this shaker is the double wall means that the ice doesn't melt as quick whilst my brain is ticking over or my vision gathers it focus on the recipe page and so its a little more forgiving than other shakers. The other great thing is that the condensation on the outside which causes pools of water on the bar is minimised.
Any critism....well... I have to admit that I have been tempt to tap the shaker on the side of sink/bar, required on other shakers, to give that authentic professional performance before releasing the magic mix but its totally unneccessary (in fact I'm sure you just look silly). Regardless I'm worried I'll do it involuntarily and dent the sides although I'm sure it can withstand a few knocks. I'm just a being a protective of my new toy.
If your budget can strech it. I'd highly recommend to the Bodum double walled manhattan glasses to go with this. Your guest can fail to be impressed and the glass would double up well for a spectacular dessert on another occasion.
I recommend this product.