program.cs

using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Jobs;
using BenchmarkDotNet.Running;
using System;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;

BenchmarkRunner.Run<PunBench>();

[SimpleJob(RuntimeMoniker.Net48), SimpleJob(RuntimeMoniker.Net80)]
public class PunBench
{
    const int OperationsPerInvoke = 512;

    [Benchmark(OperationsPerInvoke = OperationsPerInvoke, Baseline = true)]
    public uint MemoryMarshalRead()
    {
        uint total = 0;
        for (int i = 0; i < 512; i++)
        {
            total += MemoryMarshal.Read<ushort>("\r\n"u8);
        }
        return total;
    }

    [Benchmark(OperationsPerInvoke = OperationsPerInvoke)]
    public uint StaticReadonlyField()
    {
        uint total = 0;
        for (int i = 0; i < 512; i++)
        {
            total += TheField;
        }
        return total;
    }

    [Benchmark(OperationsPerInvoke = OperationsPerInvoke)]
    public uint PropertyGet()
    {
        uint total = 0;
        for (int i = 0; i < 512; i++)
        {
            total += TheProperty;
        }
        return total;
    }

    internal static readonly ushort TheField = BitConverter.IsLittleEndian ? (ushort)0x0A0D : (ushort)0x0D0A;

    private static ushort TheProperty
    {
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        get => BitConverter.IsLittleEndian ? (ushort)0x0A0D : (ushort)0x0D0A;
    }
}

results.txt

BenchmarkDotNet v0.13.12, Windows 11 (10.0.26100.1)
AMD Ryzen 9 7900X, 1 CPU, 24 logical and 12 physical cores
.NET SDK 8.0.203
  [Host]             : .NET 8.0.3 (8.0.324.11423), X64 RyuJIT AVX-512F+CD+BW+DQ+VL+VBMI
  .NET 8.0           : .NET 8.0.3 (8.0.324.11423), X64 RyuJIT AVX-512F+CD+BW+DQ+VL+VBMI
  .NET Framework 4.8 : .NET Framework 4.8.1 (4.8.9232.0), X64 RyuJIT VectorSize=256


| Method              | Job                | Runtime            | Mean      | Error     | StdDev    | Ratio | RatioSD |
|-------------------- |------------------- |------------------- |----------:|----------:|----------:|------:|--------:|
| MemoryMarshalRead   | .NET 8.0           | .NET 8.0           | 0.2072 ns | 0.0028 ns | 0.0024 ns |  1.00 |    0.00 |
| StaticReadonlyField | .NET 8.0           | .NET 8.0           | 0.2065 ns | 0.0024 ns | 0.0023 ns |  1.00 |    0.01 |
| PropertyGet         | .NET 8.0           | .NET 8.0           | 0.2039 ns | 0.0040 ns | 0.0049 ns |  0.99 |    0.03 |
|                     |                    |                    |           |           |           |       |         |
| MemoryMarshalRead   | .NET Framework 4.8 | .NET Framework 4.8 | 1.1606 ns | 0.0141 ns | 0.0132 ns |  1.00 |    0.00 |
| StaticReadonlyField | .NET Framework 4.8 | .NET Framework 4.8 | 0.2074 ns | 0.0021 ns | 0.0018 ns |  0.18 |    0.00 |
| PropertyGet         | .NET Framework 4.8 | .NET Framework 4.8 | 0.3911 ns | 0.0076 ns | 0.0071 ns |  0.34 |    0.01 |