This would help you choose which videos to download as download speeds can be very long indeed. The main reason behind this is because they don't allow the downloading of shorter clips or scenes, so downloads can be very long. Nonetheless, videos can be downloaded in lo and high resolution .WMV formats, with the higher quality versions normally playing at 720x400px. There is also Flash streaming on most new videos, but older videos don't have this facility.
In all honesty, this download business is something that I think they have to address immediately - especially so as many of these videos are roughly around the 2 hour mark in length. At least there was no download limit here but JAVModel.com has some work to do here. It doesn't have nearly so much work to do in terms of the actual videos they have on board here - in fact, they have no work to do at all! This really is a pretty impressive collection of titles and performers.
If you are not all that au fait with Japanese porn then I think this would serve as a great introduction as they touch on many of the traditional Japanese porn themes at length here. But unfortunately it will also introduce you to the main bugbear of mine when it comes to Japanese porn - pubic blurring on the women. Not all videos contain this but I would have to say that many of them do. Most of us fans of the country's porn have gotten over it by now though, so it's water off a duck's back.
JAV Model.com may trip over notably when it comes to its download speeds and options, and there is the expected censorship of the naughty bits of many of the ladies, but this is a well put together site. The collection is extensive but possibly doesn't cover many performers or titles that you haven't seen before, and their update rate is quite amazing, really. Well worth a look but get your sleeping bags out for those downloads!