What is easiest way to deal with converting 0/1 to False/True in EF 4.x?

What you can do is to have another Property to represent the Boolean representation . Decorate it with NotMapped attribute so that EF won't consider it for Mapping. Do and If condition and return true /false based on the value of Other property.

public Class Customer
{

  [NotMapped]
  public bool MyColumnBool 
  {
      get
      {
         return (MyColumn ==1);
      }
  }

  public int MyColumn {get; set;}
  // other properties

}

Another option is to return a BIT from the stored procedure so you don't need to cast anything at C# side or use any weird decoration. This means, you can cast the integer value to BIT in T-SQL like I do below:

select col1, col2, CONVERT(BIT, CASE WHEN col3 IS NULL THEN 0 ELSE 1 END) as colWithBit
FROM table1

In your ApplicationDbContext (the class that inherits from DbContext) you can use Fluent Api to convert values for the database.

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
  base.OnModelCreating(modelBuilder);
  modelBuilder.Entity<TheNameOfYourModelClass>()
    .Property(p => p.MyColumn)
    .HasConversion(
       v => v ? 1 : 0,
       v => (v == 1));
}

Now, your database will contain 1 when inserting a true for MyColumn and vice-versa. When reading from your database 1 will be converted to true and vice-versa.