ASP.NET Identity Seed a database in a console application

IdentityConsoleSeeding.cs

using Microsoft.AspNet.Identity.EntityFramework;
using Microsoft.AspNet.Identity;
using System;
using System.Data.Entity;
using System.Threading.Tasks;

namespace SeedDb
{

    public class Program
    {
        static void Main(string[] args)
        {
            var db = new MyDbContext();
            db.Database.Initialize(true);
        }
    }

    public class MyDbContext : IdentityDbContext<IdentityUser>
    {
        public MyDbContext()
            : base("DefaultConnection")
        {
        }

        static MyDbContext()
        {
            Database.SetInitializer<MyDbContext>(new ApplicationDbInitializer());
        }
    }

    public class ApplicationDbInitializer : DropCreateDatabaseAlways<MyDbContext>
    {
        protected override void Seed(MyDbContext context)
        {
            var ttime = DateTime.Now;
            for (int j = 0; j < 100; j++)
            {
                var usermanager = new AppUserManager(new AppUserStore(new MyDbContext()));

                var start = DateTime.Now;

                for (int i = 0; i < 100; i++)
                {
                    var email = "user" + ((j * 100) + i) + "@constoso.com";
                    var tempuser = new IdentityUser() { UserName = email, Email = email };

                    usermanager.Create(tempuser, "ASP+Rocks4U");
                }

                usermanager.SaveAll();
                usermanager.Dispose();
            }

            Console.WriteLine("Time taken to complete iteration all: "+(DateTime.Now - ttime));

            base.Seed(context);
        }
    }

    public class AppUserManager : UserManager<IdentityUser>
    {
        public AppUserManager(AppUserStore store)
            : base(store)
        {
        }

        public void SaveAll()
        {
            var appstore = Store as AppUserStore;

            appstore.SaveAll();
        }
    }

    public class AppUserStore : UserStore<IdentityUser>
    {
        public AppUserStore(MyDbContext ctx)
            : base(ctx)
        {
            AutoSaveChanges = false;
        }

        public void SaveAll()
        {
            Context.SaveChanges();
        }
    }
}