I'm not Mike but I still have the original PAP2T through my 3801HGV Uverse modem and have those same ports forwarded for years without the experiences you mentioned.
For the very first time, I'm using a modem/router package and so far, not a single problem with speed or anything.
In the past, I would always insist on a separate modem & router. This modem doesn't really want to be bridged and although I could do so, it is working so well that I don't want to fool with it.
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