Sounds like we've got the same boat - '04 2120 with 2 stroke 150. It still has low hours, about 80, and generally running well. A couple issues I'll be working on: The trim sender is binding so the gauge always shows the engine as being down. I freed it up when it first started happening last season, it worked for a while and then started acting up again. Not surprising since it's somewhat exposed to water sloshing up against the transom. Not sure if it's pinned into place or spring tension tracks the angle, so I'll take a closer look at it when I remove it. As mentioned in a post higher up, I've also started having an oil feed problem. Happened once last season on the day I was being hauled out for winterizing, but it started working again on its own as mysteriously as it stopped. I've picked up a new oil filter and will be replacing it, clearing out the oil lines from the remote tank to the engine tank, cleaning electrical contacts and replacing as much of the 'old' oil as practical. The filter is so small, it could clog up easily enough so I'll be putting this on my regular yearly startup routine.
Despite these few minor issues, we couldn't be happier with our Parker. The size is perfect for us, more than enough room for our day excursions and it rides well in most conditions. Barnegat Inlet can get pretty nasty, but we've always felt safe in our Parker.
John