Where the cactus flowers grow: Robert Earl Keen rocks the Rio in Santa Cruz

Halfway through Robert Earl Keen's two-hour show at the Rio, he stopped to reflect on his days as a college student and country music fan. "We only played the good stuff," he said. "Carrie Underwood! Rascal Flatts! The fragile harmonies of Sugarland!"

He was being sarcastic, of course. Keen is a favorite of fans and critics, but he's never been a Nashville insider or had much affection for mainstream country radio. His songs about outlaws, oil workers, aspiring losers and faded border towns are edgier than most anything you'll hear on 99.5 F.M.

Judging from his between-the-songs banter, he's proud of the dues he's still paying: they're a clear sign of character. At one point, he talked about the box of moldering doughnuts that remains on the tour bus after three straight months, and his band's willingness to play a gig just about anywhere, including a festival with 4,000 fans and only two motels, or a down-in-the-mouth town in Mexico, where the lack of a green room forced the band to hang out in a potholed, trash-strewn alleyway near some vomiting college students and a possible corpse. (Not surprisingly, the motel and alleyway turn up in his songs.)

In the past, he seemed uneasy with the mixed crowd he tends to draw: the "frat boys from Abilene" who come to hear the rowdier stuff, the ever-reliable KPIG contingent, the curious hipsters and the bookish folks who like his quieter, more literary material. At one point, he coolly deflected a shouted request for an early raunchy sing-along, "Copenhagen", with a quick wink and a thumbs-up gesture.

But he seemed more comfortable last night, and he wasn't afraid to mix up the formula. He threw in a great Todd Snider cover ("Play A Train Song"), and he bookended an old song ("Dreadful Selfish Crime" between two familiar Grateful Dead melodies -- an instrumental of "China Cat Sunflower" and a full-tilt performance of "I Know You Rider," a traditional folk/blues song adopted by the Dead.

The slightly rejiggered band (missing the muddy fiddling, and with an added steel guitar player) offered a cleaner, more stripped down sound. The venue seemed to make more sense in the quieter moments, but less so during the noisy rave-ups; with all those rows of seats, the fans couldn't really dance unless they joined the manic scrum of folks to the left of the stage. REK had to work extra hard to whip the crowd into the briefest display of rowdiness.

All in all, I'm glad I went to this concert, and I don't have any real regrets about naming my cat after him, either.

Even if, technically speaking, it isn't my cat.