We have also been experiencing quite a few issues with WP Engine. The most annoying are the intermittent 502 errors that we have seen during the last couple of months. Several support tickets later this is still not fixed. We changed the comment functionality to be available for logged in users only and even hardcoded a navigation menu in the footer since the support team told us that wp_nav_menu was causing the issue (?!?).

The frustrating thing is that there are quite a few fanboys that viciously attack anyone who dares to criticize WP Engine in public (probably because WP Engine received funding from Automattic), although during the last couple of days that sentiment has fortunately changed.