I'm facing a dilemma on which sprayer to get. There is no dealer near for the SP sprayers, and the Lesco is an hour away but I go in that area often. I think the Lesco backpack looks more generic so I want to get the SP. SP parts seem readily available on the internet, however I cannot find the SP3 for a reasonable price. I am leaning towards the SP1 which is a diaphragm pump. Will the SP1 do fine for normal weed control applications or should I spend the extra for an SP3 or one of the other SP models? I do not need a high pressure sprayer. How necessary is it to get a sprayer with agitation? The lesco sprayer is at least $40 cheaper than the SP....enough to rig an electric pump to it if that is possible. Also going to buy the Lesco roto-drop spreader...it seems more flexible since it drops and throws both. Anyone want to share their experiences with this spreader? I haven't been to the Lesco store yet but it looks like the spreader is about $450.