Replaced an 11 year old 1/3 hp GE disposal with this 1/2 hp model. Stayed with GE and this model type in order to avoid having to make any plumbing changes. Easily removed the old disposal and put this one in. The only problem I had was lining up the notches on the disposal to the mounting ring. After several attempts I got them together. Also, tightening the mounting ring was difficult. Put some soap or oil on the connection before you attach them. This should make it a little easier to turn the ring. The unit itself is quieter that my old one and being more powerful works better.
I'm not a regular DIY-er, but did some research online (how-tos) before attempting installation. One important note: this unit does not include a power cord, but does include some basic equipment if you want to modify your own. I ended up adapting the power cord set-up from my old disposal—it was identical to this one. All told, it took about 3 hours to install (with some help from my wire-splicing Dad), not bad for a first-timer. So far, it's a bit quieter than my previous disposal--another brand.