SP’s are better but not necessary for your situation.  We run a later model 854 not saying it’s the best but nothing wrong with it.   I’m curious on the math of the person that said you’ll spend as much on support stuff as your budget for the sprayer.  When we had a pull type we survived fine with a $1100 Centerline light bar for guidance.   Most of the time we tend out of 1000 gallon nurse tank with a Hudson valve on it. Occasionally run a second nurse tank when doing larger blocks farther away.