In all models, the Nissan Altima offers a roomy, comfortable interior, at least for front passengers. Appointments range from fairly sparse to fully loaded, with no radio for the base car and Bluetooth, navigation and backup camera at the top of the line.

Sparse is relative, of course, and there's a significant upgrade in standard features for 2009. The price-leader Altima 2.5 sedan adds power sideview mirrors, a standard trip computer and outside temperature gauge, a rear seat lock, speed-sensitive variable intermittent windshield wipers, and perhaps most significantly, standard air-conditioning with a cabin air filter.

The overall level of fit, finish, and refinement inside the Altima has improved substantially compared to pre-2007 models, and interior quality is far more competitive in the class. The available leather upholstery feels rich, and it's a big step up from the standard cloth. Soft materials are used for touches like padded armrests.

The Intelligent Key that comes with all models allows the car to be started with the key in your purse or pocket. When the key is close enough to the car, the driver starts it by pressing a red button to the right of the steering-wheel. Many owners find these systems convenient, but you can wind up with a dead battery if you inadvertently press the start button two times instead of once to shut down the car. That leaves the system in the accessories mode, and it can eventually drain the juice. We prefer traditional keys.

The front seats in the Nissan Altima sedan are relatively large. They feel firm, and longer and higher than those in previous models. They also have optional power lumbar support and elevate substantially, allowing a better view between all the SUVs on the road. The seats in the Coupe are unique, with more aggressive bolsters befitting this model's sporty aspirations. There's adequate thigh support.

Beyond the seats, most interior parts are common to the sedan and coupe, starting with the dashboard. It's functional, without being boring, and stylish without being frilly. The round air registers in the center of the dash would be better if they could be shut like the rectangular ones at each end.

The four-spoke steering-wheel has an original, artistic design, with two spokes flowing vertically downward. The gauges are arranged in a practical tripod shape, with speedometer in the center, tachometer on the left, and fuel gauge and water temperature on the right. The lettering is sharp, white on black, with red needles. LCD insets display trip information, outside temperature, safety-related data, and personalized settings.

The center stack is neatly designed, with three big HVAC (heating, ventilation, air conditioning) knobs at the bottom. They're easy to understand and operate. Controls for the base and up-level audio systems sit just above the heater knobs, and they're friendly to the eye and fingers. The base audio system, with single CD player, is satisfactory. The nine-speaker Bose upgrade sounds particularly rich.

The optional navigation system features a 6.5-inch touch-screen above the audio controls. It also allows voice commands, but some features are tricky to learn. Without the owner's manual, we would not have been able to begin to figure out how to make real-time traffic information work. Not even with a passenger devoted to the challenge while we were stuck in traffic. Pay attention during the post-sale walkaround or study your owner's manual.

The shift lever occupies the forward portion of the center console separating the front bucket seats. Altimas with the continuously variable transmission have a foot-operated parking brake, but the gear selector is slightly awkward for using the manual shift feature. Cars with a manual transmission have a handbrake next to the shifter. Even when it's not engaged, the handbrake sits up at just about the right height to trip the bottom of a coffee cup as it's lifted out of one of the cupholders situated between the shift lever and the bi-level center storage bin.

The primary storage space inside the Nissan Altima is the glovebox. It's huge, and it locks, so you can store a laptop computer in there. There's also a storage bin with a hinged cover at the bottom of the center stack. The problem is that the only power point accessible for plugging in a radar detector is tucked deep inside this bin, and it stretches for all but the longest coiled cord. The fixed pockets in each front door are too small for maps, but they have molds that fit half-liter water bottles. That's nice, because tall, thin bottles are too small for the center console holders, where they flop this way and that through the mildest maneuvers. There are two more cup holders in the rear seat.

The Altima sedan's rear seat is roomy enough for two good-sized adults traveling to dinner or the movies, though we're not sure about a cross-country trek. The center seat is best left to age 12 or less. Access to the rear seat is easy, in the sedan.

The coupe is a slightly different story. Its front-passenger seatback has a release lever on the inboard side that allows the driver to ease passenger access to the rear seat. That access isn't particularly awkward, because the lever folds the seatback and slides the entire front-passenger seat forward in its track. Only problem is that the front seat forgets its settings, returning to a pre-set, default position in its track and seatback angle. Seeing as how coupes costing the same and even less than the Altima have seats that manage to remember the settings, this is inexcusable.

Once a passenger is settled in the Coupe's back seat, the change in exterior dimensions is obvious. Most of the Coupe's four-inch reduction in wheelbase translates to a decrease in rear-seat legroom, and this isn't a place most adults will want to spend more than 20 or 30 minutes. The Altima Coupe is a coupe, to be sure, and tighter rear-seat space is probably expected. Still, it seems tighter in the Altima than in the .

In trunk room, the Nissan Altima sedan is competitive in its class, with 15.3 cubic feet of space. Thanks to a relatively short trunk lid, though, a lot of that space stretches forward under the rear parcel shelf. The Altima Coupe isn't really in the game. It's 7.4-cubic-foot trunk is substantially out-spaced by the Accord Coupe (12.8 cubic feet).