After years of staying onsite (DLH & PP) as well as trying out many Harbour hotels we found the Anabella about 15 years ago. Fell in love with it and the location. At that time, we felt that if not staying onsite then the walk (especially at the end of the day) felt like you were still in the bubble - DTD, exit through GCH, lower traffic on DL drive, the pathway and lights on the trees. It’s a bit nicer transition for the senses than the jump right to Harbour - for us annyway, YMMV. Also the Anabella was almost its own compound as well, keeping out traffic noise, they had pool movie nights, etc. When they tore down the Anabella and put in the Westin we were sad (sentimental) but also interested in the new. We’ve stayed at the Westin twice since then and bought into DVC at Grand Cal. As mentioned by a poster above, the overall room costs (onsite and to some degree offsite) helped in the decision of going into DVC.
For us, if we can’t get into our DVC, or have dates on either end, the Westin is definitely choice #1.