It depends on amount of data. You can use 1 weel constructor for a light wheigt. It will be faster to assembly than 4 weels. BUT if you have a bigger weight you will bring it faster then 1 weel constructor. Time of assembly + time of delivery

For Example

THIS IS FASTER AbsoluteTiming[Table[Length[Solve[x^i == 5 y, x]], {i, 1, 5, 1}];]

THAN THIS AbsoluteTiming[ParallelTable[Length[Solve[x^i == 5 y, x]], {i, 1, 5, 1}];]

BUT!

This is SLOWER AbsoluteTiming[Table[Length[Solve[x^i == 5 y, x]], {i, 1, 100, 1}];]

THAN THIS AbsoluteTiming[ParallelTable[Length[Solve[x^i == 5 y, x]], {i, 1, 100, 1}];]

It depends on amount of data. You can use 1 weel constructor for a light wheigt. It will be faster to assembly than 4 weels. BUT if you have a bigger weight you will bring it faster then 1 weel constructor. Time of assembly + time of delivery

For Example

THIS IS FASTER AbsoluteTiming[Table[Length[Solve[x^i == 5 y, x]], {i, 1, 5, 1}];]

THAN THIS AbsoluteTiming[ParallelTable[Length[Solve[x^i == 5 y, x]], {i, 1, 5, 1}];]

BUT!

This is SLOWER AbsoluteTiming[Table[Length[Solve[x^i == 5 y, x]], {i, 1, 100, 1}];]

THAN THIS AbsoluteTiming[ParallelTable[Length[Solve[x^i == 5 y, x]], {i, 1, 100, 1}];]

Hastings 2015 Hands on Wolfram... "Note that increasing the number of CPU cores might not result in an exact linear speedup, since some extra time can be spent for scheduling the calculation and putting the results together."