I am not sure if you would find any "scientific" findings on the subject of proximity to high-voltage, John, however I myself would prefer a view unfettered by wires...whether they cause health problems or not!
"A survey administered in 1990 suggests that proximity to high voltage power lines is being capitalized into lower values for residential properties. Respondents who had appraised such property report that power lines can affect residential property value to varying degrees under certain circumstances and that the market value of these properties is, on average, 10.01% lower than the market value for comparable properties not subject to the influence of high voltage power lines. Further, the results indicate that even appraisers who had not appraised such property believe that power lines contribute negatively to property value."
Hope this helps!