>>3719321You should go with an intuos medium size. Its basically industry standard and offers the best quality for the money you can spend. This tablet survives when you upgrade or break your pc too, unlike the alrernatives.
The ipad is a good alternative for on the fly sketching, but still worse quality than the intuos. Personally decided against buying one despite traveling a lot, because apple is notorious for phasing out older models by draining the battery with software updates.
For a built in pc there is the surface and the wacom mobile, they are out of your budget. The price you pay for portable device is not worth it, both for actual money and for the loss in quality.