I'm about to get into different lenses. Are the cheaper lenses even worth buying? I'm considering buying pic related because of the current cashback option (CHF 165 instead of 215). Or should I directly start spending 700+ bucks or even 1000+? I know that money doesn't imply quality but I'd try to go for the best value in the respective price range.

I currently own the EOS 700D with the kit lens and was looking for a somewhat wider lens. If you have concrete suggestions in the <18mm range, I'm happy to listen.