Here it is in a "nut shell" based on I have personally experienced (flown) with the same type of engine (YS 45 RE)
The Diamond Dust (standard wing) and the Whiplash deltas have about the same top speed level flight. The Whiplash is cleaner but heavier and only faster out of a dive. It is more rugged. Unfortunately it is no longer made and was expensive.
The Diamond Dust can make a much harder 90 degree direction changes than the Whiplash because its lighter and it won't high speed stall, perhaps the most violent, sudden 90* than any other aircraft. The Diamond Dust will hopefully be available again soon. For maximum maneuvering and aircraft survival when using high output 45 or larger engines, you must use high torque, high speed, high dollar servos on these two deltas. The Dust's battery area's floor must be reinforced!
The Screamin Demon may be every bit as good as the other two deltas, but I haven't seen or tried one and it is available.
The Outlaw is a bit slower and smaller in size and engine (OS 32) than the other deltas, but it can do more. It's high speed roll rate and high speed flat spin is outrageous a.k.a "Kentucky Pile driver".
The Viper 500, a quickie 500 pylon racing plane, is slower than the first two deltas. Its roll rate is poor. It may not make as hard a 90 degree turn as the Dust, but it will carry the speed though 180 degree turns or loops much, much better. Blink and the loop has just happened. The Viper should have some easy mods done.
I had a shrike 40 arf (w/ landing gear) and it was slower than everything that I have mentioned except the Outlaw. It was the hardest to land (Land it hot or it stalls) and it could not turn near as hard as any of the others because the wings would high speed stall with a lot of up elevator. It did have the highest roll rate of any plane I’ve flown or seen. Just a blur in the sky.
I have an Ultra Sport 40 kit still in the box. Looking at the drawings it would take some mods to keep it together if you do aggressive maneuvers with a large Jett on it.
----------------Fun Factor----Shock Factor-----Speed Thrill
Whiplash-----------8---------------6-----------------10
Diamond Dust------9--------------10-----------------10
Outlaw-------------10-------------10------------------8
Viper 500-----------8--------------9------------------9
Shrike 40 arf--------7--------------6-------------------8
These are only my opinions and you won't change my mind until I’ve seen otherwise.
Others may have had different results