What's Santa's budget? What type of Cork do you use?
If you are taller, the additional height of the Italian is worth it. Note: there is a Red and Burgundy version of the Portugese. The Burgundy is 3" taller, and made of rounded vs extruded steel.
Some of the corkers (and it is corker specific, and not model specific) have problems with scoring synthetic corks. If you use synthetic corks, one solution might be to seal the top with wax.
If you are bottling beer, then it might make a difference to you that the Italian has a Capper attachment.
If you notice, on both the Italian and Portuguese, the plunger (pointy thing) is mounted to the arm and swings on an arc. That means, the plunger puts a slightly diagonal pressure on the cork.
If Santa is generous, you might want to consider the Swiss Rapid Corker. For a mere 7 times the cost of the Italian, you get better machine. It has a separately mounted plunger, so it goes straight down onto the cork. It is also built like a tank. I found one at a much discounted price on Craigslist. Note: It does not disassemble like the Italian or Portugese, so shipping is a bear.
IMHO:
Consider the Burgundy Portugese first. It is on sale until 10/31 for $65, about the regular price of the Red:
http://www.winemakersdepot.com/Corkers-C191.aspx
If you are making beer, then Italian is the way to go. Note: The Italian can be found used for a little more than the Portuguese ($75 if you are willing to wait and look around).
If you have a generous benefactor, or come across one used, then Swiss is the one to put on your list.