Samsung p7510 versus p5110 : what are the main differences? I'm in a tight schedule to buy someone a tablet in the ipad2-range, but I want to buy an Android device.

After some research I decided to buy the Samsung Tab  10.1" P5110 (I don't need 3G).  However the Samsung Tab 10.1" p7510 is much easier to find in a short term.  When comparing both I got a bit confused because I don't get the main differences between both models.  

Is there an obvious 'best one' ?
P5110 is the Galaxy Tab 2 while P7510 is the original. The difference is that the newer ships with ICS and has a different SoC along with a slightly larger battery, while it is a lightly ticker. The P7510 came out almost a year ago.  

If you want future software upgrades the P5110 is a safer bet. See that datasheets for more info.