The biggest benefit to a higher end charger is a bigger wattage budget. The majority of sub 50$ chargers have a wattage of 50 or less. This really comes into play if your charging larger cell count packs,

Recently picked up a Gens Ace IMars charger, which offers 300 watts on each channel when using an external DC PSU. My backup chargers are ISDT branded units, and they work pretty good. If your racing 2wd buggy, pretty much anything will work. 8 volts at 6amps, which would be a pretty common charge rate for 2s lipo packs works out to 48watts. If your charging 4/6S packs, at 6amp you need between 100 and 200 watts.

My suggestion would be to pick up something in the 100$ range, and purchase a used HP server power supply. Then do the conversion to get a rock solid PSU. Dont use A/C for the supply source.