We tested the drives in both types of mode - closed session, where a 'track' of data is written to the disc in one go, and packet write, where chunks of data are written 'on the fly'. The format used is shown in brackets next to each drive. For example, (-R) is DVD-R and (-RAM) is DVD-RAM, and so on.

We used the software supplied with each drive and timed each write operation, in seconds, using the same chunk of data (ensuring that any caches were emptied first). Note that for the Panasonic and Sony drives there's more than one entry, because each can cope with several different kinds of write operation. In each graph, a lower bar represents a shorter time to write the data, and so a faster drive.