throat hit and smoothness are opposites.. none of your choices are the best anyway.. but the bigger classic style will give smoothness and tatse.. the smaller RN4075 like a 901 but not a 901 will give more harshness and throat bite..
how hot the heater coil in the atomizer runs play a big part in this.. cool means smooth hot means harsh.. take you pick..
the RN4075 mini style runs hotter than the same style DSE901 at the normal voltage..
trog