I have an LG that I like. It has all the buttons on the bottom, instead of on the side, which was great when my kids were younger and shorter, and wanted to warm up their hot chocolate or pop popcorn. The buttons on the bottom also mean that the microwave is wider than normal. It has pre-programmed buttons for things like softening butter (which I use ALL the time), ice cream, frozen OJ, cream cheese.
About the installation - my husband did it himself, while I hovered. The hardest part of installation, IMO, is the bulk and weight of the microwave. Ours came with very clear directions and was simple and easy. Of course, we simply replaced the existing microwave - not sure if you'll have to wire anything extra because you're doing a new installation.