I've just started using it and after a few teething troubles am now getting on fine with it. I didn't particularly like the "letterbox" view that appears for some questions. I e-mailed my concerns to the company and got a quick and helpful response - they are addressing this issue, but they also suggested viewing the pages in a specifically designed mobile format (option on log on page), which I prefer anyway. And this is great for doing a quick test on your mobile phone if you've got a few minutes spare! The pages are quick to load, as are pop-ups, and flow freely.
The site isn't fancy (though it says they are upgrading some of the statistics features), but it is very usable - it is a bank of questions, which is what it's supposed to be, isn't it? There are very few explanations, but I prefer that as it makes me get my books out and read not just the very specific bits relating to a particular question but the areas around it too - surely better for overall understanding, which is what I want when I'm flying.
I have no experience of other QBs, so cannot compare, but at £9.99 for 100 days (special offer on at the moment) I think it is excellent value and, for me, it adds another dimension to my studying which keeps me interested without dominating other resources.
Hope that was of some help. PP
