oh dear. i smashed up my A4 sized 'Trust' tablet and pen last week. if i hadn't been so angry at the time i would have put it to one side and considered giving it away - meaning i could have sent it to you as a gift. oh well, too late now.
why did i smash it up (yes, pen snapped in half and tablet split into several pieces)?
it was unreliable. i only plugged it in when i needed it (usb). i'd have to change the options each time i did this but i didn't mind. but then it just refused to work one day. i checked the battery in the pen - perfect. i tried unplugging it plugging it back in a few times - no difference. so i decided it must hate me - so i killed it.
if it had been a wacom tablet i wouldn't have destroyed it - because of the cost they are. 'Trust' products are always bargain priced so this A4 tablet was about £50 ($100) which is a great deal less than a Wacom A4 sized tablet.
Admittedly, the Trust tablet only had about 512 levels or sensitivity - half of the current Wacoms. does that matter? i think it doesn't matter at all. when using these types of pens i've never seen anything that would demonstrate 512 (or double) the levels or pressure being translated onto the screen. they look like they've got about 12 levels of pressure to me, i.e they are nothing like using a real life pencil with all the subtlety that allows. mouser sent me an older Wacom tablet a few years back and i wasn't impressed by that either (i can't remember now which DC member received it after me).
another thing that annoys me about tablets is the poor 'absolute' positioning they have. to me this should translate to one inch moved across the tablet with the pen should equal one inch moved across my monitor with the cursor - but it doesn't. maybe new Wacoms can be adjusted to perfection, i've not had the privilege of using one.
i see many artists using Wacoms online and producing brilliant pieces of work so i know that you can get good results - you adapt to the tool in hand and learn to compensate for its shortcomings, of course. so i hope to do the same when i eventually buy a new wacom tablet. hopefully i'll be able to test drive one before i buy it as i really don't want to waste money on something that is going to work exactly the same as a £50 Trust tablet but costs six times as much (i know Wacoms have many more features but i don't think they are worth six times the price).
another thing about tablets, i don't think they are all they are cracked up to be. if you are painting/drawing/sketching within a program like photoshop it makes sense. if all you are doing is drawing selections around parts of an image and doing a few other non painterly type edits then a tablet it pretty pointless.
i've seen one or two friends buy a tablet (Trust) only to be frustrated when they realised they had better control using a mouse. they found it difficult to coordinate with the pen and tablet and for how much they were going to use it (just drawing selections around peoples head, etc) they'd never master it - so back to the mouse they went.
i can draw kinda okay just using the mouse. i can't apply different levels of pressure but after using a tablet i'd say so what. a tablet doesn't allow me to apply the same levels of pressure a pencil does.
from using the Trust and the old Wacom tablet i'd say using these things is like using a fat bendy ink pen whilst wearing thick leather gloves that restrict your finger movement. in other words, they are crap compared to real pens (and paint brushes). but, again, the art i've seen online obviously means people are more than capable of getting brilliant results from them - though, i think this is mainly because of all the other editing features you get from using software like layers, dodging/burning, masking and undo - which can be done with a mouse. obviously using a tablet and pen will be quicker for drawing but i find them bad for navigating around your operating system - double clicking and all that can be awkward (hence the double click button on all pens).
i really, really, hope that when i finally get around to buying a new Wacom i'm blown away by how responsive it is. if you're going to be doing detailed paintings then maybe a Wacom really is going to be essential but i would put money on a decent artist being able to get exactly the same results from a bottom of the line budget tablet and pen.
my advice, try the Genius first.