Unity persistent data script

IAPManager.cs

// basic persistant data saving and loading: https://unity3d.com/learn/tutorials/topics/scripting/persistence-saving-and-loading-data

using UnityEngine;
using System.Collections;
using UnityEngine.UI;
using System;
using System.Runtime.Serialization.Formatters.Binary;
using System.IO;

public class IAPManager : MonoBehaviour {

	public bool _isProductCleared = false;
	bool _isPremium = false;
	public Text _label;
	const string FILE_PATH = "/playerInfo.dat";
	public static IAPManager _iapManager;

	void Awake () {
		if (_iapManager == null) {
			DontDestroyOnLoad (this.gameObject);
			_iapManager = this;
		} else if (_iapManager != this) {
			Destroy (this.gameObject);
		}
	}

	void Start () {
		if (_isProductCleared) {			
			DeleteFile ();
		}
		Load ();
		IAPStatus ();
	}

	public void IAPBought () {
		_isPremium = true;
		IAPStatus ();
		Save ();
	}

	void IAPStatus () {
		if (_isPremium) {
			_label.text = "IAP Purchased\n";
		} else {
			_label.text = "-------------";
		}
	}

	public void Save () {
		BinaryFormatter bf = new BinaryFormatter ();
		FileStream file = File.Create (Application.persistentDataPath + FILE_PATH);

		PlayerData data = new PlayerData ();
		data.isPremium = _isPremium;

		bf.Serialize (file, data);
		file.Close ();
	}

	public void Load () {
		if (File.Exists ((Application.persistentDataPath + FILE_PATH))) {
			BinaryFormatter bf = new BinaryFormatter ();
			FileStream file = File.Open (Application.persistentDataPath + FILE_PATH, FileMode.Open);
			PlayerData data = bf.Deserialize (file) as PlayerData;
			file.Close ();

			_isPremium = data.isPremium;
		}
	}

	public void DeleteFile () {
		if (File.Exists ((Application.persistentDataPath + FILE_PATH))) {
			File.Delete((Application.persistentDataPath + FILE_PATH));
			_label.text = "-------------";
		} 
	}

	public bool IsPremium () {
		if (_isPremium) {
			IAPStatus ();
		}

		return _isPremium;
	}
}

[Serializable]
class PlayerData {
	public bool isPremium;
}