Hi and welcome,
I think you got BOClean wrong. Its approach is unique but not in that it's behaviour-based, it is signatures-based and it has no heuristics. (I think. At least I'm sure that it's mainly signatures-based.) Now, until you think BOC is same old:
Its unique approach is that instead of playing cat and mouse around your hard drive with malware, it doesn't act until a program (any one) is loaded onto memory to run. Then it compares the code injected into memory with its database. So no matter how good a piece of malware is at hiding and reproducing, if it wants to be run it's going to have to get past BOClean's scrutiny. Plus at that time polymorphic malware has its "pants down" so it can be detected without need of comparing it with its every possible mutation. (The malicious code in question must be written to RAM in order to be run.) This is a very good approach since +90 per cent of even 0-day threats are variants of previously existing malware.
BOClean also does an additional memory check every few seconds but I can't explain you what is it about because I don't know. Also as you must surely know BOClean does all this using very few resources.
Reportedly BOClean's whole functionality will be included in the final release of CAVS. But even then it will continue to be available as a standalone product.
Hope this helps.
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