Re your Misto sprayer: I do not have the Mistos but have been using a
Pampered Chef Kitchen Spritzer (4 in fact) for 2-3 years. I believe they
work on similar principles. Other than occasional cleaning with hot, soapy
water, the secret for me is releasing the pressure after each use. Just
twist the top ring to release then retighten. This lets the oil trapped in
the take-up tube drain back into the reservoir & not sit & get thick &
gluey. Also, do not store near a heat source, even the fridge. Heat makes
oil thicken. Good luck.
Sherry in Charlotte