im happy with my flytron openlrs, flash it with openlrsng firmware, and make some dipole antennas and your good to go. i have only gone 2 km (need a bigger flying feald) but i still had 100% rssi.
have a look at hawkeye lrs to. its based on openlrs with a few hardware improvements and its preflashed with openlrsng. i have not used it so i cant comment on its performance.