I have experienced flawless RC operation with both BlueRail (bluetooth) and LionChiefPlus, track or battery powered. With so many after-market systems available, I can understand that there might be some problems encountered.
On another subject, one of the issues with battery power is the difficulty in recharging. Each of my battery powered engines have a battery access jack which allows me to monitor voltage and recharge without having to remove the battery. However, on-track recharging would still be more convenient and I plan to look into this idea.