I have at least 60 custom decks, including a bunch of wonderful decks I acquired from Theory 11. I went through a period of "obsession," unable to stop myself from buying custom decks. There is no "Decks Anonymous." Finally, I was able to bring my habit somewhat under control. Well, certainly there are worse and more expensive "addictions" and I really enjoy bringing them out and doing magic and flourishes with them, and showing them off.
I look at the decks and boxes as works of art.
All of that being said, when I perform professionally, I usually use Bicycle Rider Backs. They handle, spread, fan and spring beautifully, they are durable and the quality is consistently excellent. People generally recognize them and are less likely to think they are "trick" cards. Besides, I want my regular deck and my ID to look the same - even the color of the backs. For really upscale bookings, I use the custom cards because they are classy, make a great impression and are often admired and remarked upon by the guests.