In summary, the TwinMOS TwiSTER PC4000 512MB Dual Channel kit does what it says on the box. That puts it on a par with other PC4000 modules we've tested. What sets it apart from the other heavyweight premium manufacturers is price. It's cheaper and just as good. Indeed it managed to run at PC4200 speeds without too much difficulty. If you can appreciate the knowledge that high-speed modules, and we're talking PC3700 upwards here, aren't partial to ultra-low latencies, the TwinMOS set provides that best value. That sounds contradictory when 512MB costs £110, but that's the state of play in this niche market.