For the past 10 years I have been on a desktop, loved and hated it. Due to my increase in mobility I have just bought a MacBook and love it. Its portability that got me, I could just sit in one particular spot for a long time, even if I'm still in the house I can sit by the fireplace or have it in the kitchen when I'm cooking etc.
However I still kept my desktop computer for playing games and I still love it.
I prefer Laptop (Powerful one) , it will be expensive but very nice as it will go with me anywhere , and I can't leave the computer , but at all I only have a desktop . Laptops have a problem which is that its hard to change their contents .