I loved my Ninja. Notice I said "loved" because I broke two of them. I used them for smoothies in the morning. Killed the motor in the first one after about 6 months. Called customer service, the guy tried to tell me it was my fault, and I was following the instructions, so it wasn't. It was a Christmas gift, so after I fussed and mussed, he agreed to send me a new base for free, and then it took over a month for me to get it because it was "backordered." I highly doubt it was backordered, because they are all over the shelves in the store. The replacement one lasted about a year. Same thing, I killed the motor.
I would love a Vitamix, but can't justify the expense. Although, if you buy enough cheap blenders, you have dang near bought a Vitamix. I ended up getting a KitchenAid 1500 on sale at Kohl's for around $115-$130, and it works even better than the Ninja. I LOVE it.
And yes, the Ninja blades are very sharp and can be a pain to clean. Also, the pitcher for it has a lot of seams, where the handle comes together and the handle meets the body, and is oddly open on the bottom and the handle is hollow. Which means if you're hurrying to get it out the door in the morning, and rinse and don't wash until later, the water gets up in the there with the little food bits you rinsed and funky stuff happens. Even when you do wash right away, water gets stuck up in there. No good.
Nan