I bought the bamboo medium tablet as a beginners tablet (previous model). I think it's great and I'm still learning to use it. However I have the opportunity to buy a used intuos3 A5 for ~$100, but am unsure if it's worth the upgrade. According to specs it has a higher surface resolution and it detects pen angle (bamboo doesn't) and the active surface is about the same. The main reason I'm considering it is because I like sketching digitally and the beter resolution might make that easier. Is it worth the upgrade?