You are going to get a lot of feedback on that.
I have ridden a few and owned a few. TPE has been making those motors longer that E Tech. E Tech has been building motors for years. It all depends on who you trust, how you ride, and your particular preference. Who will give the best advise for your tuning and riding ability, who you can afford, and when you require it. Are you buying all parts from one supplier and doing all they say to do to tune it, or using existing parts and tuning yourself? What is your skill set currently tuning and riding, what do you hope to attain with the new motor package?