Some direct comparisons, based on similar engines. Data taken from Wiki.

Burnelli UB14

Engines: 2 P&W Hornets (750 hp ea)

Empty wt: 9200 lbs

Gross wt: 17,500 lbs

Max Speed: 210 mph

Range: 1240 mi

Sevice ceiling: 22,000 feet

Lockheed Model 14

Engines: 2 Wright SGR-1820-F62 760 hp ea

Empty wt: 10,750 lbs

Gross wt: 17,500 lbs

Max Speed: 250 mph

Range: 2125 mi

Sevice ceiling: 24,500 feet

Martin B-10B

Engines: 2 × Wright R-1820-33 775 hp each

Empty wt: 9681 lbs

Gross wt: 16,400 lbs

Max Speed: 213 mph

Range: 1240 mi

Sevice ceiling: 24,200 feet

WINNER: Lockheed

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Burnelli CBY-3

Engines: 2 Pratt & Whitney Twin-Wasp R-1830 1,200 hp each

Empty wt: 16,900 lbs

Gross wt: 27,000 lbs

Capacity: 24 passengers

Max Speed: 237 mph

Range: 1025 mi

Sevice ceiling: 24,000 feet

Douglas C-47 Skytrain

Engines: 2 Pratt & Whitney Twin-Wasp R-1830 1,200 hp each

Empty wt: 18,135 lbs

Gross wt: 31,000 lbs

Capacity: 28 troops

Max Speed: 224 mph

Range: 1600 mi

Sevice ceiling: 26,400 feet

WINNER: Douglas

For such a *vastly* and *obviously* better design, the performance of *actual* Burnelli aircraft was unspectacular.