Some users welcome the competition. "Primavera isn't ideal for my business anymore," says Oswaldo Manangon, senior project engineer, Kiska Construction Inc., Long Island City, N.Y.

Manangon says Primavera's older, discontinued P3 product was a great fit, but its P6 targets other markets, such as IT project management. Furthermore, it extends the capability of the software "beyond the needs of construction."

Shawn Pressley, CTO at Hill International, Marlton, N.J., which uses both Asta and Primavera, says one of Oracle's vulnerabilities is that "it makes everything seem more technical than it needs to be. Asta is a nice, competitive solution. It's back down to the basics of scheduling a project—similar to P6 but with more P3," Pressley says.

Both Asta and Primavera have roots in construction. Oracle bought Primavera Systems Inc. in 2008 from Joel Koppelman and Faris, who invented and launched it in 1983. Asta was designed by contractors and introduced in Europe in 1988; it is used around the world, except in North America.