I use an Aptek A4 not that expensive and could not be without it for much of my work esp. masks and local fine adjustment.
It does feel weird at first, and forget worrying about handwriting!!! the more accurate the tablet the worse it will look-but thats not how you work with tablets.
The other thing that puts people of using them is that you have to trvel right across the pad to select brushes etc. and after years of the mouse it seems awkward stretching across the tablet to select a brush for example.
Thats partly why I use A4 but because of how you integrate with the tablet, its ample size and only specialist graphic use requires anything larger- I am a digital artist and daw and paint with my tablet as well as photo work and A4 is fine.
I have the mouse handy as well so for general selection meneu acess etc i use the mouse, only using the tablet when I need the control and FEEL it brings.
As you use the pen and tablet you very quickly switch off from the physical, you do not look at your tablet you look at the screen. You become engrossed in the brush work fine detail and it all becomes very natural as if you are painting directly on to the screen. Any possible idiosyncrasies mentioned above become irrelevant, as your total absorption is on what you see on screen you compensate without thought- it all becomes free flow your eyes direct your movement and you respond without thought of anything mechanical and certainly not the tablet!
It does feel very awkward at 1st, think how many years you have used a mouse. But use the mouse for the basic stuff and the tablet for the finer more detailed stuff. A4 I find best, A3 to big A5 bit restrictive. The Apteck is fantastic value and has already stated above take time to set pressure etc to your style.
Pretty soon you will find yourself using the tablet for more things and getting absorbed in in the process, not the mechanics, it really does feel like you are using brushes and pens directly ton your photograph via the screen just as if you were working on a hard copy.
You will also find that there are many techniques and process that you avoided without thought as to why- and generally you have not tried or not used because the mouse lacks the control needed that you now use on a regular basis because the belt gives you the control and interface that the mouse cannot.
My signature is xexexexe, but I am an artist, traditional and digital, very very few artists have ever had good handwriting, we simply find writing boring and to be swept through as quickly as possible - my signature is basicaly just my intials can't be bothered with the letters in between!!!
Rather pleased. So far very useful for content aware fill brush in Photoshop, esp for things like telegraph wires. 
Linear Mode
