I-26 or I-85 to Greenville, SC

Thanks for your responses. I never really thought of taking I-40 West from Statesville, but may do that, and hit 321 down to I-85. I have travelled I-77 many times and don't mind the Fancy Gap decline into NC, unless you hit it during a foggy time period. I came up it one morning, before daylight, and could not see 6 feet in front of me. We are not leaving until this coming Tues. PM, and heading to the Western panhandle of FL. I don't mind driving in hilly country-one road we take up to Canaan Valley, WV area, has a 9% grade. The only problem with those steep grades is that I am probably only getting 2-3 mpg.