I have this one and I like it a lot because it's easy for me to hold. I eventually off the metal piece on the end of it (for hanging up or something) because it rattled and the noise annoyed me. But it's pretty strong and fairly quiet especially compared to my old one.
I have this one. Best investment ever. Gusto likes it so much better than clippers (Meg is not impressed and continues to be clipped). The charge lasts forever for me. I do maybe 5 minutes at a time (turning it on and off as I go, not running the whole time) a couple of times a week, and I don't think I've charged it in a month. The speed is super adjustable, not just '2-speed', so I'm able to put it at whatever speed Gusto is okay with.
I don't find it particularly heavy or hard to handle, even with the battery. I think a cord would also work for us at this point, although in the beginning it would have been hard, as we were moving around a lot as I worked on him.