It has been perfect for me. I have not run across the thing I wanted it to do that it couldn't with the exception of playing iTunes purchased movies (yet). I don't need/want cameras, 3G, or a 10 inch screen on my tablet. I don't need bluetooth, but I would find uses for it if it were available. I just need access to the Android Market to get the apps I need and for those apps to work. In every occasion for myself, so far, it has done that. I am just rooted stock and using the Zeam Launcer and it has been the perfect little tablet. I actually prefer the 7in form factor because it fits in the lab coat pocket I wear at work and in a zippable portfolio I already carry.
Now in your case, I think I would just make the Tab work. Either rooting it to make it work. I am surprised you can't get it to sync. I am curious exactly what kind of problems you are having? It should be able to do everything the Nook can do. And that is what it comes down to, you already have the Tab and I don't think that the nook will do much different or Sync differently so I would look into why you are having trouble with the Tab first, it is an expensive thing to have around if it doesn't do what you want. My phone is the Samsung Captivate and it does most of the things I want so maybe you can use some of the things I use on the captivate and nook to help solve your problems.
For syncing music on both I use iSyncer to get music from my iTunes. iSyncer wifi is also very nice to sync from your comp to the nook wirelessly. I use dropbox for a lot of documents or if I want them available offline I just drag and drop.