I bought three spools of black Makerfarm ABS 3mm filament on EBay for $8/1kg spool, plus shipping (came out to $31 total). I am having some delamination problems on taller prints (like a Mendel90 X motor mount) that I wasn't having, at the same speed and temp settings, with the Filamex brand filament I usually buy, though the outside finish is generally nicer with the Makerfarm stuff. I am running my bed at 100 degrees with hair spray (it doesn't seem to stick as well to ABS slug as the Filamex does), hotend at 235 degrees, speed of 60 (30 on first layer), 0.4mm nozzle on an E3D-V6 (Mendel90 printer).
Any suggestions?