I currently own a Nikon D3000 with an 18-55 and 55-200 lens.
I am looking to purchase a lens to minimize switching out lens. I am looking at the Sigma 18-250 and Nikon 18-200. The price difference is about $400 which is pushing me towards the Sigma, however, I don't want to end up with a poor quality lens.
Keep in mind, I am taking pictures as a hobby/memory keeping. I am taking pictures of my family, at birthday parties, soccer games, and vacation etc. I obviously want quality results but I need to know if the price difference to the Nikon will give me that.

Additionally - Should I keep the two lens I currently own or trade them in. Husband seems to think I should keep the 55-200 even though I am looking at the 18-200/18-250.

Thank you for your feeback!