What is the best RO membrane for brackish water? with TDS 5000 ppm

DOW FILMTEC™ Brackish Water RO Elements with a 8-inch diameter provide consistently high performance, enhance element life period, enabling lower energy usage and reduced costs.

TDS range of what is considered brackish water is roughly-,mg/l.Above that the water is considered saline and below it is fresh.Both RO and ED technologies are  able to treat brackish water.RO is usually the preferred solution nowadays.ED is considered economically viable only for low salinity range