Virtual appliance technology can come in many forms: software, hardware, open vs. proprietary. eWeek Channel Insider Technology Editor Frank Ohlhorst sifts through the options. The pros for virtual appliances: lower costs; faster deployment; disaster recovery and business continuity; easy upgrades; many deployment options. The advantages of proprietary hardware: definable performance levels; control of hardware and software; plug and play deployment; hardened operating systems; failover and load balancing; single vendor support for support or troubleshooting. What's better? Neither, but guidelines include the size of the deployment; the anticipated growth; the business model; budget.