I went from a Monster 1100 to my Hyper 1100. For me, the decision was based on an ergonomics issue. The Monster was too much like a sport bike and caused problems for my bad hip. The Hyper on the other hand, is insanely comfortable to me and feels more like a "standard" riding position.
The downside honestly to the Hyper is the effects of wind at higher speeds. I found that anything above 75-80 and I really have to hang on to the bars or it feels like the wind will pull me off. I can tuck in some, I even got a small windscreen, but they really don't help that much. Extended freeway riding at 70ish is fine, but anything above that and I find I get tired of getting knocked around.
Also, I fine I use all six gears too. Granted 6th is only after 70+ mph, but its great for gas milage when I commute for work some days. Short blasts over 70 are way fun too. It seems to me that this bike really is at its best when ridden under 100 MPH.
Even with all that power, the Hyper just feels easy to ride for some reason. Maybe its sitting upright and up so high. I really feel like I can see everything going on much better than I ever did on the Monster. Even the standard brakes (same as what were on my standard Monster) are confidence inspiring. Took me a little bit to get use to riding with the balls of my feet on the pegs, but now its very comfortable.
Off the top of my head, thats about it