Very happy with this scanner. For scanning letters, bills etc before shredding, it's perfect. The battery power + (micro) SD card operation means you can just whip it out when you need it, then at some later time sort out all your files. Being able to create either PDFs (or JPGs) directly is very handy for this, since I like to store scanned letters as PDFs. It's a pity it only creates one page PDFs though - it would be neat if it could create multi-page ones.
If I recall correctly the B&W mode is actually greyscale - in my opinion it's more useful being greyscale.
Power on takes a few seconds. Scanning is straightforward enough, just press the big scan button and it's immediately ready for you to drag it across the page. It has a series of rubberised rollers across its width. These are all linked together so when you scan they keep you tracking in a straight line. It tells you if you're going too fast - according to the manual, I've not scanned anything too fast yet. In grey and low resolution you can scan a page in a few seconds which is plenty fast enough I think. I haven't experienced any frustration getting quite good results - but if you're worried about distortion or getting the *exact* area you're expecting, then you won't be buying a handheld scanner, right!
It appears as a USB drive when plugged in and that's the most convenient way to get scans off. Or eject the micro SD card - handy to put stuff on the tablet PC or phone.
The colour screen is not great resolution or colour reproduction but it's clear and bright enough and you can zoom in up to 5x and that generally seems to be enough to tell you whether you've got a good scan or not (the first few scans I used this to checked them all, but they seemed to come out okay and I don't bother checking now unless I really need a good scan). Navigating around the scan with the buttons is quick and intuitive enough. The screen also gives you a basic menu - for example to change settings and to format the micro SD card.
One quirk is that you need to turn the power on when it's in USB mode (for getting scans off). Another is that at the start of a scan pages can get caught up in a channel between the glass platen and the body of the scanner, causing you to make a jerky scan at the beginning as the page folds over a bit. That said, it's usually a part of the page that's plain white, so doesn't seem to show up in the scan. And like all of these handheld scanners, the actual scannable width doesn't extend right to the end, so if you can't flatten a book you want to scan then you can't get right to the edge of the page.