I'm an UI designer. Just tried yesterday, my feelings

Love + UI is clean and lightweight, but bugs in inspector; + love the corner-radius handler + repeated group is also handy

Want + Ingredient with adobe products ( ai/ps) +linked files like Indesign; so that GUI designers can focus on the graphic asserts with ps/ai, and I can focus on interaction with xd + Easy export + one thing I love most about sketch is how easy it can be to export pngs. + Symbols + makes life a lot easier to reuse symbols + More animation