Love this product. I use it in conjunction with a couple of mascaras and it works perfectly with each. It helps to make the mascara last longer and also makes my lashes grow a bit and feel really soft. I agree with Sue that it makes your mascara work harder, you need much less and get a better result!
Not sure whether anything can condition eyelashes but this product is the very best bulking undercoat for any mascara. Apply, let it dry for a minute or so then apply your favourite mascara and watch your eyes open up. It helps prevent mascara getting on bottom lashes without touching the skin inderneath and it takes on waterproofing properties from such mascara. Makes expensive premium brands of mascara more economic as you need less coats.