MAC 24-7 Bar + Restaurant, the new all-day, all-night eatery in the Hilton Waikiki Prince Kuhio Hotel, is a place of playful, and sometimes puzzling, contrasts. MAC stands for "modern American cuisine." But the menu is retro diner.

The view out the walls of windows — into the warmly wooded lobby and onto a garden of hala, palms and shrubbery — is all Hawai'i. But inside, it's London's SoHo or New York's Chelsea or some other foodie district. The design is sophisticated and spare, with splashes of bright color (orange suede walls, purple panels, silver bead wall hangings) against a background of neutral taupe, slick white tablewear in every shape but round, waiters in rumpled futuristic uniforms of tunics and cargo pants.

It's a hotel coffee shop. But it's also angling for the people of the night — particularly those who are looking for huge troughs of hangover-preventing food. (Though word of the month-old spot doesn't appear to have reached them; the place was awfully quiet on three different evenings when we checked in.)

So should you defy your ingrained resistance to entering Waikiki and check this place out?

On the plus side, parking: They validate; all you need to do is tip. Smart move.

Also on the plus side, architectural interest. There is not another room like this in the Islands. Masterminded by cb5 Restaurant Group, whose portfolio is a paean to hip one-name restaurants around the country (Beach, Bleu, Pao, Tatu), it's as edgy and now as a Vogue photo shoot. Go see it.

On the plus side for some, but not for me: portion sizes/pricing. The amount of comfort food chef Rey Desalla piles on a plate is astounding. I ordered white cheddar mac and cheese ($12), ate a playing card-size portion, forked some over to my friends, then went home and weighed the leftover tray. It weighed 17 ounces! Our friend ordered fried chicken ($16), and it was fully half a chicken, plus waffles and a boat full of gravy (more on this later).

At breakfast, the waitress took one look at my (much reduced) frame and warned me off the mac daddy pancakes (six types, $11); they're 14 inches across and three per order. Comfort, indeed, if you're into grinding mightily. But for the likes of me, this restaurant should consider half-orders. Or quarter orders.

The menu, on a single half sheet, is half breakfast, half not. The lineup is interesting and enticing, but the execution hits and misses. The absolute hit is the meatloaf (again, half a loaf pan on a platter, with garlic mash and gravy covered with Eryngii mushrooms from Hamakua; $16). This is better than Mom used to make: firm texture, satisfying flavor and the the gravy is really a refined sauce. Have this!

Two appetizers, in the "small plates" section of the menu, went down very easily. The charmingly named "cocktail party" ($15) recalled the finger food of the '60s: five dainty Swedish meatballs in a lovely brown sauce; five crab-stuffed mushrooms and, least successful to me but my husband woofed 'em, a half-dozen uninteresting longanisa sausages wrapped in puff pastry — dogs in blankets, Manila-style. Husband also had to have crispy rock shrimp and calamari ($12). These deep-fried dainties arrived in a paper cone in an upright spiral holder with a generous side of rich remoulade sauce, the spicy mixture that results when Thousand Island dressing visits Cajun country. Crispy, creamy, yum.

My girlfriend's classic reuben on marble rye with kraut ($13) was good and actually not monstrously big, though with a sizeable side of crisp fries.

Breakfast definitely works: Smiling service; excellent coffee in your own little round pot; buttery cinnamon rolls (a six-pack of smallish ones for $6), the best, beefy, smoky burger I've ever had in a loco moco ($13), with brown sauce and mushrooms; and light-as-air pancakes (thank God, because they're the size of area rugs) in interesting flavors. We had the Elvis, with peanut butter swirled with bacon.

But two dishes at dinner were misses, and there was oddness about the drinks menu.

The waitress said there was no wine list; they were still "working on it" and she had very little to offer — chardonnay, sauvignon blanc, cabernet and merlot, one each, at $5 a glass.

We were very curious about the fried chicken with waffles and country gravy. And very disappointed. The breading was just wrong (and I can say that because my daddy was from Water Valley, Miss., and, honey chile, I KNOW fried chicken) — dry and overcrisp on the outside with a soggy under-layer. The chicken itself was tender and nicely flavored, but my friend literally had to peel off the breading to enjoy it. The waffles needed more body to stand up to the gravy.

My mac and cheese included some nice period touches, such as breadcrumbs on top and peas inside (Mom, trying to sneak some vegetables into you). But there was almost no flavor — certainly nothing approaching that of a sharp white cheddar — and an odd, slick texture. It also arrived in an intimidatingly large family-size serving bowl with nothing on the side. By the third bite, I was craving a carrot. (Yes, Mom, you read correctly.)

Savvy by now to portion sizes, we four shared two cupcakes: devil's food-peanut butter cup with shiny fudge frosting ($6) and warm chocolate lava ($6). Neither rang our chimes. We were told that the devil's food would be "filled" with peanut butter, but had to dig for the small knob of crunchy-sweet peanut butter it contained. And the cake that surrounded the warm chocolate lava was dry, while the lava tasted as though someone had picked up the salt shaker instead of the sugar that night. Needs work.

Despite that, I'll go back to MAC 24-7 because it's an interesting place, and I want to see how it fares, and how the fare improves.

Reach Wanda A. Adams at wadams@honoluluadvertiser.com.