This paper illustrates performance and best practice of compact multiphase metering systems that have been operating for 2-years in the light-oil steamflood pilot in Minas-Sumatra. These results motivate the need for life-cycle risk models integrating new technologies to meet customer needs. In some cases, low-cost new-technology may not be the best choice. If multiphase metering systems are suitable, then a unified systems' vendor should be included on the team during all phases of the project, especially early on to support quality assurance during integration of sub-systems, and later during commission and operation to support quality control of the complete metering package. In this paper, we present two similar types metering systems for two different types of applications: 1) well-test measurement, and 2) bulk production measurement. Both metering systems are of the partial separation type and use a compact gas-liquid cylindrical cyclone separator, or GLCC© (copyright by The University of Tulsa, 1994). When constructed these were the largest GLCCs and are still believed to be the largest operating GLCCs in the world. After the produced fluids are separated into individual gas and liquid streams, each stream is volumetrically metered and then recombined. The liquid level in the separator is controlled by an innovative gas-liquid dual-mode control scheme. For water-cut measurement, the well-test system uses an on-line instrument whereas the bulk metering system uses a physical fluid measurement based on sampling and analyses. Field data and suggested modifications to achieve suitable operation are presented. In particular, we focus on the impact and uncertainty of higher than expected sand concentration, watercut, flowrate, pressure & temperature on the original design, and consequently discuss the specific changes we made to address these challenges.