I feel very similarly about that deck (and combo decks in general), and have also been playing about as long as you have. It's cool to see them in action, but it definitely leaves you with this feeling of "what could i have done?" after losing to it.
That said, I played against a Turtle Mage the other day and their combo did *not* go well at all. I could sense their frustration. I almost felt bad for winning that match.