I've ridden most of the bikes that do not require the manual operation of a clutch. I currently have a 2009 Yamaha TMAX, 2007 Yamaha FJR AE, and just bought a DN-01. In the past I've had a BMW C650, 2004 Honda Silverwing, 2006 Suzuki Burgman 650, 2009 Suzuki Burgman 650 and a Paggio BV 250. I've also ridden many 125 and 150cc scooter.
IMHO, the DN-01 is the least practical of all the bikes I've owned. It has zero storage, is hard to put a luggage rack on, has fiberglass over the gas tank so you can't use a tank bag. It's also not the fastest, not the most maneuverable through With all that said why did I buy it? It's one of the most beautiful and coolest looking bikes ever made in my opinion. Also while not the fastest it's not a dead dog and it's easy to handle everything about it.
Of the others I can tell you my thoughts. In many ways the Burgman 650 is a great bike. It's fast enough and it can do hills and turns quite well. It has more storage then any bike I've ridden. It's downfalls are that it's extremely complex and expensive to pay for repairs. It has design defects that make them break in ways that are hyper difficult or expensive to repair. Worst of all perhaps is that Suzuki is a scumbag company that doesn't stand behind it's warranty or recall known defects. I'll never give Suzuki money again!
The Honda Silverwing 600 was a fine bike that I rode for 30,000 miles with only maintenance. It has basically as much storage as the Burgman 650. It's downfalls are that it has small wheels that make it hard to be good in the hills and turns as well as making me less confident in maneuvers. It's Honda rock solid reliable and if you're vertically challenge the low seat height is good.
The 2009 Yamaha TMAX rides the best of all these maxi-scooters. It really is a sport scooter. It has less under seat storage then the Silverwing or Burgman 650 but still workable. It will do turns in a way that can compete with sport bikes and it can be improved a little with Dr. Pulley sliders. It's tallest a problem for the vertically challenged. It's worst side for me is that it's slightly under powered. Mine is done in the mid 90s MPH and it accelerates fairly poorly over 80 MPH. I do a lot of cross country and on rural expressways this creates a little challenge.
The BMW C 650 GT is a fine bike. It is a traditional CVT with a chain in an oil bath instead of a belt. It has every option you can think of like heated grips and seat, TPMS, and basically every computer thing you can imagine other then GPS as part of the dash. It's very tall for the vertically challenged, but can do hills and turns quite well. It also has a little more horsepower then the other Maxi-Scooters 60 BHP. The seat is somewhat uncomfortable at long distance and the maintenance schedule is high. All in all a fine bike for those with a 32" inseam or longer.
The 2007 Yamaha FJR AE is a wonderful bike. BTW they (Yamaha) made AE or AS electronically operated clutch bike for the USA in 2006 through 2009 and that they still make them for sale in Europe. It's identical to the manual FJR except there is no clutch lever as the YCCS computer operates the clutch for you when you change gears and that it has a hand operated paddle shifter as well as the normal foot peg. It's a 630 lbs five speed with an in-line 4 1300 that produces more power then you can ever use. It can accelerate from 65 MPH to 130 MPH in about 3 seconds with a top speed of near 150 MPH. It's very highway worthy and can do hills and turns better then I have the balls to do them. It comes from the factory with hard side cases that each fit a full face helmet and can easily take a Givi E 55 topcase or luggage rack, also you can have a big magnetic tank bag. As stock it's a little too sport bike in some ways. Namely that the bars are too down and forward making you have to lean too much of your weight on your arms (fix with Heli bridge bar riser). The seat sucks but there are numerous after market seats that help this go away (I have a Russel Day Long). Also the foot pegs are slightly back. A custom seat and risers help the foot peg problem by making me sit a little more upright and you can add highway pegs for another foot position. Since you don't need to use the foot shifter you can put on highway pegs and ride with your feet on them all the time. You just need to use your right heel instead of your right toes for the rear brake. The FJR is the choice of bikes for the Ironbutt Association for their most insane endurance rides so you know it is extremely durable. It's just not as pretty and easy as the shorter and lighter bikes like DN-01
If I could only have one of these bikes it would be the FJR 1300 AE. If you are a true motorcyclist with bad legs you should look at an 06-09 FJR AE. I've had five of them in the last eight years. A long story but I liked each and every one. Also Yamaha really stands behind their product. My first FJR AE was an 06 that I bought in 2010 with 9,000 miles on it. When it had 35,000 miles a year after I bought it the bike broke down with the electrical system going crazy. I brought it to the Yamaha dealer who ripped out and replaced the main electrical harness along with checking and repairing other wiring at no cost to me. They said that Yamaha was taking responsibility for all electrical and harness problems in 06-09 FJRs for life due to the electrical recall they had.
Compare that to my 09 Burgman 650 where the stopper bolt broke at 10 months old with 28,000 miles and the Suzuki dealer literally disassembled the bike into a frame with bushel baskets of parts after a month and then called to tell me that Suzuki was refusing to pay to repair my bike. they said that even tough it was still in warranty that anyone who rode it 28,000 miles in ten months must have abused the machine. I liked the way that the Burgman rode well enough that I was fooled into buying a used 2006 with 3,000 miles on it in 2012. Two years later the main electrical harness burnt out and the repair was more expensive then the value of the bike. I ended up selling it to a DIY guy for a thousand dollars as is. BTW the BMW C-650 was rear ended and wrecked while waiting stopped for traffic and the Silverwing is still alive and well with the owner I sold it to, as are a couple ofFJRs.