I'm looking for a decent tablet to use for my hobby drawing. So I need something that is a decent replacement for pen and paper and has a good life time (minimum 2 years). I was interested in Wacom's Intuos 4 but heard it's nibs spend too easily.
If you can afford wacom intuos, buy it.
If lifetime is a big concern then even more if not already, wacom is the choice. They have most accessories available ( especially for intuos )
Also, the lifetime for one pen nib is around 1 year depending on how much you use it and how you use it aand what pen nibs you use. ( one pen nib can last from one year to +4 depending on how heavy user you are )
My pesonal favorite and the most long lasting pen nib is the stroke nib. ( they sell these separately in packs of 5 which more or less means 5 years ) Without checking details for intuos 4, the package does include at least one of these stroke nibs.
Also they do sell overlays separately as well. Those may peel like onions in heavy usage.