I can't speak specifically about 4runners, but working at a dealer I've seen the good and bad. Like I said I can't speak of 4runners, but for other manufacturers I'e seen numerous problems with ignition switch/security problems with autostart brand stuff. I've also had problems with the remote starters that ziebart uses. (I can't remember the name). I've never really had any issues with the viper or OEM stuff. Surprisingly, not to many issues to speak of with the lower line bulldog stuff either. The few problems I've seen with bulldogs typically is due to installation error. (bad crimp point leading to high resistance by the ignition switch leading to security/no start issues). My guess is the reason I've really seen no issues with viper and lots of issues with auto start and the ziebart brand stuff is partly due to the fact that viper most likely makes their installation techs maintain a lower comeback percentage and higher CSI to allow them to continue to sell their brand I can't confirm this, just a possibility.
I've seen good range with both the bulldog and viper. If there is ever a problem holding it to your chin helps amplify the signal.