Rounded and resized in 2008 to hold more luggage and give its five passengers even more breathing room, the Scion xB (the largest of the three Scion models) gets a more powerful standard stereo – a Pioneer unit with 160 watts and a display menu – for 2010.

A 200-watt Alpine stereo is new, too, as is a removable navigation unit from Alpine, and both are optional. Scion excels in offering accessories that are timely and desirable to its youthful buyers; in fact, its portable GPS navigation units have reached the sophistication levels of much more expensive built-in navigation systems available in luxury cars.

The xB is well equipped at its base price. Other than selecting optional alloy wheels, there are few other options, save the electronics, that can substantially increase the xB’s base $16,420 MSRP. Standard at this price are antilock brakes, stability control, a manual transmission and airbags front and side. Optional is a four-speed automatic transmission, as well as a DVD player for the enormous rear seat area.

This latest xB is stretched a foot longer, and its roofline is lowered, giving it more of an angular look than the nearly square original xB, for which there was such a large assortment of accessories that two never looked the same.

The larger xB’s 158 hp 2.4-liter twin-cam four-cylinder (also found in the sharp Scion tC coupe) is willing and returns a respectable 22 mpg in EPA city testing and 28 on the highway. The new xB will launch quickly from a stop and get to 60 mph in less than nine seconds.

Gauges are placed in the center of the xB instrument panel, which works well for a number of small cars. Scion parent company Toyota has used this arrangement in small cars for years, and it quickly becomes habit.

Critics give the interior design of the xB good marks. Audio and climate controls are simple to find and operate, and they’re placed high on the dashboard, making them easy and intuitive to reach. Optional is colored interior illumination that also lights up the cupholders. In addition, colorful pedal covers are available, as they are on other Scions.

The xB is much softer riding on the highway than the original pre-2008 “boxmobile,” so it won’t upset the driver or four passengers. The calm and quiet driving manners of the 2010 Scion xB make a comfy place to listen to its cool audio systems.

If you’re ready to roll, the xB will delight.