Not to sound like a cheesy Hallmark ad, but what matters on a journey is the people you share it with, not the destination. This is true of almost all road trips, especially ones of the cinematic variety. The best road trip movies ("Planes, Trains and Automobiles," "Rain Man") seat viewers with characters we're happy to spend time with, eager to see them grow and evolve by journey's end.

On the other hand, the bad ones ("Due Date," "All About Steve") give us companions we'd rather run over with a car than share a ride in one.

"The Guilt Trip" pleasantly falls somewhere in middle of those two extremes, with the operative part of that sentence being the word "pleasant." Stars Barbara Streisand and Seth Rogen don't play the most exciting or dynamic travelers in film history, but they, along with the entire movie, provide a nice time, and not the boring kind of nice that will make you start counting the sprinkles on your Sno-Caps for entertainment. Or, as I like to call it, "Playing for Keeps" syndrome.

Rogen plays Andy Brewster, an inventor attempting to peddle his all-natural cleaning solution, Scioclean, to any big-box store that will listen – including Costco, which has now appeared in more movies this year than credits. He's planned a trip to hit several corporations across the nation, but after visiting his doting New Jersey mother (Streisand) and learning about an old flame of hers now in San Francisco, he decides to take her along for the ride. Clingy hijinks ensue.

The typical road trip movie rigmarole would take the two characters and put them into a series of contrived scenarios for humor's sake, usually caused by the comedic sidekick's freakishly annoying ineptitude. Thankfully, "The Guilt Trip" avoids the genre's usually tedious conventions, sidestepping big, ridiculous set piece moments and instead focusing on the bond between mother and son, strained by the former's nagging and the latter's stubbornness.

If you have a mother, Streisand and Rogen's conversations will sound pretty familiar, with motherly advice responded to with mindless nods and short answers. A few times, writer Dan Fogelman (who co-wrote last year's "Crazy, Stupid, Love") tries a bit too hard to dredge humor from their relationship, but for the most part, he has a great feel for genuine mother-son interactions. Her nagging never seems like too much, his annoyance is always understandable and the emotional moments barely feel cloying. It creates drama without sacrificing the characters' humanity.

It's good that the script stays on point because if not, it would've been a waste of two engaging leads. Playing against his shlubby manchild role, Rogen is far more reserved but no less charming as the awkward, easily-flustered Andy. The Apatow alum also still thankfully knows his way around a toss-off line or hilarious rant.

Streisand, in her first non-Focker role of the new millennium, is every bit his equal (as you'd expect from the veteran actress). Every time she gets close to overdoing the stereotypical Jewish concerned mother routine, she nicely pulls on the reins and keeps the character away from caricature. Together, the two appealingly sell the comedy, as well as the emotion.

Admittedly, the affable duo's road adventure doesn't go anywhere particularly new. In fact, it's safe to say most audiences will see the story's developments from several miles away (something made even easier by the blatant music cues for emotional moments). It's this predictability, combined with the movie's relatively safe, subdued dramatic and comedic stylings, that steers the film dangerously close to blandness.

With worse actors in the lead roles, "The Guilt Trip" could've been a cinematic flat tire. Instead, Streisand and Rogen make the most out of the film's low-key charms, resulting in a ride worth taking. For added impact, bring Mom.