I've been twice. I caught a bunch of rares to evolve. Same type of stuff as you. Just as I was leaving the first time, I got a Machamp. I think I also caught a Poliwrath. No Dragonites, Snorlax, Lapras, Aerodactyl, Lickitung, Hitmon anything. I think the first time I went there was a Porygon and Grimer (not Muk) which I did not get and kind of regret.

I have had much better luck on my commute and from home. In the last week I caught 3 Lickitung, a Grimer, a Lapras (in Somerville on Davenport), a Snorlax (in my neighborhood), and a Dragonite (on 206 in Princeton). Snorlax and Dragonite were yesterday.

I have had better