I recognize that Canola, Vegetable, and Corn oil are all Vegetable-Based oils, but many Recipes call for different kinds of oil. I don't know why. Is there a major taste/other difference between Vegetable, Corn, and Canola Oil? Is there any reason why I couldn't just use Canola for everything?  I know of many popular types of cooking oil including: Soy Bean, Coconut, Olive, Palm, Corn, Vegetable, and Canola. There are so many, and I don't want to have 7 different containers of oil.  Are there a few that I really need to have? How are they different and what should I use them for? 
You may try a mango pit remover. Slide the peach up as far towards the small size as possible. This is just a thought, I have not tried it. 