I did not mention Linux at all. This discussion is about VRPC, wich only runs on Windows ATM (discounting Wine). And the VM system of Windows is crap, we all know that.
The point is, that most of the time RISC OS does not need the HDD at all. In fact it was designed to work without any discs at all. The fact that it currently has no substantial disc caching does not mean that I was wrong. Windows needs HDDs for its operation and uses them a lot. So to lessen the extreme HDD usage a little, they had to implement disc caching. RISC OS never had this problem in the first place, because it only ever uses the HDD to load applications and do user-requested operations like saving and loading files or doing searches. The way to do "disc caching" on RISC OS is to put the files you want to work on onto the RAM disc. The RISC OS way to do it also reduces the risc of getting corrupted files in case of a power-failure and gives the users the feeling that they are in control over their machine. With Windows the average user never knows why the hard disc is doing something when he is not doing anything at all. This is probably one of the reasons why PC users are so suspicius of Microsoft.