I've stayed four times now at the Alcobas. All on points so may not be the same experience for the typical suite purchaser in this forum. But FWIW...
I've warmed up to the rooms vs my original post on the LA master thread. Still a couple annoying things like light switch placement, but truly quibbles. At a macro level the hard product is great. spacious rooms, great shower and toiletries, and a very relaxing patio with firepit. Know that there are three types of rooms. The vineyard-facing rooms, the "creek" or "winery" facing rooms which really face the beringer parking lot and a few that can be quite close to highway 29, and the rooms in the main house, which i've not seen but pictures suggest not all have outdoor space let alone the fire pits. Pool is fine but somewhat self serve. There are waiters for food and drink though.
I still find the soft product a bit off. They try but it's just not quite there. The "front desk" is in a little hut adjoining the main house. Not an issue for check in as they just bring you to the room. But checkout can be a bit cramped. Not well thought out. Breakfast is tasty and on the website the continental breakfast is included on virtually all rates but the staff sometimes thinks otherwise and I have to pull out my confirmation to show that it is in fact included in reservation rate. There is a shuttle service. We called one night to get picked up in downtown St. Helena after dinner and were denied at 9:50 because the driver stops at 10:00. I understand 10:00 is 10:00 but feel other properties would have been fine with finishing at 10:05. No other real blatant call-outs, but all four times i have left with the sense that this is not firing on all cylinders like I have experienced at similarly priced properties such as the St Regis aspen or the Park Hyatt Paris. I've not tried the concierge.
I do like that it is walking distance to main st. in St. Helena, which i enjoy more than downtown Yountville (other than better restaurants in Yountville, but that is what uber is for). It has a more local and accessible vibe.
Bottom line is it's a great hotel but i feel overpriced for what it is, driven by the relative lack of competition vs. demand for high end properties in the heart of the valley floor. If your focus is on location and hard product you'll be satisfied. If you are prioritizing check in to check out pampering and over the top service like the christmas tree installation upthread, be prepared you might be disappointed.