I'm not familiar with receivers with antennas 100% internal, but on many setups the biggest issue with range i see are due to antenna placement.

For example raising active part of antenna on my infraction substantially increased range.

Some futaba owners that speed run swear air receivers running antennas at angle gives best range, but I'm kinda skeptical.

if you want higher end radio i suspect something like futaba 7px will give really good range if active part of your receiver antenna is not blocked by lipo/ carbon fiber parts and you move transmitter antenna in vertical position. I use 4px and like it, but it sounds like you might want something higher end. Obviously some speculation on my part since i don't own that radio, just basing that off of modulation, antenna placement, transmitter design. It has several design features in common with the cheaper 4px.




some of this information is incorrect, unless there is new method to transmit rf without an antenna that I'm not familiar with.