Between the 2 up there I go for the He-219. In my opinion it was the better of the 2 aircraft. Some He-219 varients had a whopping armament consisting of Two 30mm Mk 108 Cannon in wing roots.
Two 20mm MG 151/20 Cannon in belly tray.
Two 30mm Mk 103 Cannon in belly tray.
Two 30mm Mk 108 cannon in Shräge Musik mount.
Ammunition: 100 rounds per gun
The thing I dont like about the P-61 is the fact that it was heavy and quite big, but then agian so was the Ju-88.
Here is a comparison of the 2 aircraft:
He-219
Origin: Ernst Heinkel AG
Type: Night fighter
Models: He 219A-0 to A-7, B and C series
Crew: Two
First Flight: He 219V-1 November 15, 1942
Service Delivery:
Prototypes: November 15, 1942
He 219A-1: November 1943
Total Production: 268
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Powerplant:
He 219V-1:
Model: Daimler-Benz DB 603AS
Type: Inverted-vee-12 liquid-cooled
Number: Two Horsepower: 1,750 hp
Typical:
Model: Daimler-Benz DB 603G
Type: Inverted-vee-12 liquid-cooled
Number: Two Horsepower: 1,900 hp
He 219A-6:
Model: Daimler-Benz DB 603L
Type: Inverted-vee-12 liquid-cooled
Number: Two Horsepower: 1,750 hp
He 219A-7/R2:
Model: Daimler-Benz DB 603E Number: Two
Type: Inverted-vee-12 liquid-cooled
Horsepower:
1,800 hp at 2,700 rpm for takeoff.
1,900 hp at 5,905 ft. (1,800m).
1,550 hp at 22,965 ft. (7,000m).
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Dimensions: He 219A-7
Span: 60 ft. 8 in. (18.5m)
Length (With Aerials): 50 ft. 11¾ in. (15.54m)
Height: 13 ft. 5½ in. (4.1m)
Weights: He 219A-7
Empty: 24,692 lb (11,200 kg)
Loaded: 33,730 lb. (15,200 kg)
Performance: He 219A-7
Maximum speed: 416 mph (670km/h)
Initial climb: 1,804 ft (550m)/min
Service ceiling: 41,660 ft (12,700m)
Range: 1,243 miles (2,000km)
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Armament:
He 219V-1
Two 20mm MG 151/20 Cannon in wing roots.
One 13mm MG 131 in rear cockpit.
He 219A-2/R1
Two 20mm MG 151/20 Cannon in wing roots.
Two or Four 20mm MG 151/20 Cannon in belly tray.
Two 30mm Mk 108 cannon in Shräge Musik mount.
He 219A-7/R1
Two 30mm Mk 108 Cannon in wing roots.
Two 20mm MG 151/20 Cannon in belly tray.
Two 30mm Mk 103 Cannon in belly tray.
Two 30mm Mk 108 cannon in Shräge Musik mount.
Ammunition: 100 rounds per gun
He 219A-7/R2
Two 30mm Mk 108 Cannon in wing roots.
Two 20mm MG 151/20 Cannon in belly tray.
Two 30mm Mk 108 Cannon in belly tray.
Two 30mm Mk 108 cannon in Shräge Musik mount.
Ammunition: 100 rounds per gun
P-61 Black Widow
GENERAL INFORMATION:
Type:
P-61: Three-seat Night Fighter
F-15: Two-seat strategic reconaissance
Manufacturer: Northrop
Models: P-61A thru C, F-15 (RF-61C) Reporter
First Flight: May 21, 1942 (XP-61)
Service Delivery:
May 1944 (P-61A)
1946 (F-15A)
Final Delivery: N/A
Total Produced: 941 (plus 35 photo-recon versions)
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POWERPLANT:
Model: Pratt & Whitney R-2800 Double Wasp
Type: 18-Cyl 2-Row Radials
Horsepower (P-61A): 2,000hp R-2800-10
Horsepower (P-61B): 2,000hp R-2800-65
Horsepower (P-61C and F-15): 2,800hp R-2800-73
FUEL:
Capacity: N/A
Type: N/A
DIMENSIONS:
Wing span: 20.12m (66 ft.)
Length (P-61A): 14.92m (48 ft. 11 in.)
Length (P-61B & C): 15.1m (49 ft. 7 in.)
Length (F-15): 15.3m (50 ft. 3 in.)
Height: 4.49m (14 ft. 8 in.)
Wing Surface Area: N/A
WEIGHTS:
Empty (Typical P-61): 10,886kg (24,000 lbs.)
Empty (F-15): 9,979kg (22,000 lbs.)
Maximum, Loaded (P-61A): 14,696kg (32,400 lbs.)
Maximum, Loaded (P-61B): 17,237kg (38,000 lbs.)
Maximum, Loaded (P-61C): 18,280kg (40,300 lbs.)
Maximum, Clean (F-15): 12,700kg (28,000 lbs.)
PERFORMANCE:
Maximum Speed (P-61A & B): 366 mph (590 km/h)
Maximum Speed (P-61C): 430 mph (692 km/h)
Maximum Speed (F-15): 440 mph (708 km/h)
Initial climb (P-61A & B): 2,200 ft. (670 m) per minute
Initial climb (P-61C & F-15): 3,000 ft. (914 m) per minute
Service Ceiling (P-61A & B): 33,000 ft. (10,060 m)
Service Ceiling (P-61C & F-15): 41,000 ft. (12,500 m)
Range - Max. Fuel (P-61A): 500 Miles (2360 km)
Range - Max. Fuel (P-61B & C): 2,800 Miles (4500 km)
Range - Max. Fuel (F-15): 4,000 Miles (6440 km)
ARMAMENTS:
Four 20mm M-2 Cannon in belly, fixed forward.
Plus
Electric Dorsal turret with four .50 machine guns, remotely controlled
from front or rear sight station and fired by pilot.
(in first 37 A's, last 250 B's and all C's)
Plus (B & C Only)
Wing racks for 6,400 lb. ordnance load.
F-15 carried no armament.
For the most part, there performance was equal however the the He-219 had better armament. Between the 2 I go for the He-219 based off performance, looks, and design and the fact that Luftwaffe Night Fighter tactics generally were better.
Now having said that I think the Ju-88 was a much better night fighter than both of those combined. 