Never had an Otterbox, but I can say that I love my Lifeproof.
What I really love about the company is their customer service. Whenever we have had an issue with the cases, they are so helpful in either replacing them or just helping us out.
I have the purple one right now, but I really want the green one. Hopefully soon I will buy it, but it's just a lot of money and I don't want to spend it :lol-sign:
The lifeproof felt bulky to me and I didn't like having to unplug and use an adaptor for my headphones. That said I have broken several otterbox cases so I have complaints all around. lol
FYI - if you have original Apple headphones, you don't have to use the adapter. They fit perfectly into the case. Took me like a year to figure that out, but yep, it works!
Does the Lifeproof case come off easily if I only want to use it sometimes?
It isn't too hard to take on and off. However, they recommend not to take it off often at all.