The Poly tower 1B with that extra bathroom is REALLY nice. I have stayed at PIT in a deluxe studio twice now (resort view and theme park view,) but always do the tour of the 1B and 2B (when it's available to view,) and think they've really nailed the room utilization in the tower in all categories. Those Tower Studios, or Duo Studios, or whatever they call them, are WAY better than the Riviera ones, too. If you ever wanted to host grandparents or adults tagging along who want some privacy/have different sleep times, they're great options for lower points. You definitely will need to own at Poly to book those.
I believe there's only a handful of the resort view 1B and 2B, so you're smart to get a fixed week contract for that room category so you can set it and forget it. The PIT (Poly Island Tower) itself is great, but we really missed not having a QS option and sundries shop on site. The pocket gardens (samosas? samoas?) are very nice and peaceful. We enjoyed the fireworks up there with a bottle of wine, and it was cute with the little kids watching in their jammies around us.
Pros for PIT versus GCH is that it's not a far walk to GCH and the monorail and Captain Cook's, and you're definitely more removed from the chaos of GCH. Wailulu is awesome! I hope they expand the menu to breakfast and a few more options for dinner and lunch, but what they do have is very good. I'm just greedy and want more of it! The freestyle machine by the bathrooms/pool is really nice, and I appreciated the wash sink there for rinsing out the mugs/Stanleys.
Cons are it's still Poly and BUSY all the time on the grounds and pools. Definitely culture shock for us coming from Riviera and Animal Kingdom, which are never that crazy with little kids running all over, LOL. If you want the original Poly studios that sleep five, God bless ya, but those are not for us. We like a 1B and a door, unless it's a couple's trip.