About a year ago, I bought a low miles 1987 Suzuki Savage for my wife. The Savage (also known as the Boulevard S40) is an underrated and misunderstood bike. It is a light and simple single cylinder 650cc cruiser-style bike, with belt drive and a 4 speed transmission. Its target market sees that it is a 650, and assumes it is too big and powerful. People considering 650cc bikes find the Savage underpowered.
Ignore the displacement of the engine--rather than comparing to other 650cc bikes, compare it to bikes with similar seat height, weight and horsepower. (I've never understood focusing on displacement rather than power and weight) This puts it in the upper end of the 250 class of bikes--low seat height, similar weight, a bit more horsepower and lots more torque.
Horsepower is responsible for top speed, and also for acceleration when driven hard, and is likely to get inexperienced riders in trouble.. Torque is responsible for off the line and everyday performance when you aren't thrashing the bike. More torque makes starting and shifting easier--if you let the clutch out too fast, it may chug and complain, but it isn't likely to stall.
The early Savage models had a 4 speed transmission, while later models are 5 speed. The 5th gear was added for marketing purposes--basically top gear was raised a tiny amount and another gear slipped in between 3rd and top. This requires an extra shift, but with the torque curve of this engine there's no advantage from the extra gear.
I'm not a fan of cruiser styling in general, but that's taste rather than a valid criticism. It does allow forward controls, which let the seat height be low enough for almost any adult while leaving enough room for a 6 foot rider. (The Savage is a bit cramped for me but rideable. The Honda Rebel is just plain too small) The tank-mounted gauges are a significant sacrifice in usability to gain an uncluttered handlebar area--the gauges are well out of the rider's normal line of sight requiring a deliberate look down instead of being visible with a quick glance, especially with a full face helmet. This is especially problematic for the turn signals--when I ride with my wife, I'm constantly reminding her on the intercom to turn the signal off. (I'm going to add a beeper, or a light she can see) Another flaw is the lack of either a fuel gauge or trip odometer--every bike should have at least one. No tachometer, but on this bike not really needed.