First let me correct my spelling: it is Patscheiderhof.
Having now taken my trip, and eaten at both restaurants, I though I'd reply to my own post in case anyone else has a similar query in future.
Both restaurants do traditional cooking with well sourced ingredients, both have outside seating on terraces with panoramic views.
Signaterhof appeared to be just the cook and his wife, who does front of house for the restaurant and their B&B. We split three primi and a secondo because the primi seemed more interesting than the secondi, most of which were quite plainly cooked meat. We had:
gnocchi filled with cheese - light and very generously cheesy
home made spinach ravioli - really excellent, in this area the spinach filling seems to be spinach with onion and garlic, very unlike the spinach and ricotta you get further south
trio of canederli (beetroot, cheese and spinach) the canederli here and at Patscheiderhof were noticeably lighter and better than others we had in random places. But we couldn't quite warm to the traditional manner of serving them as a primi with butter and cheese, which was too dry and bready for our tastes. We much preferred them served as a side to mop up the sauce in a secondo, or floating in soup.
gerostl - sauted potatoes and beef, served with a tasty side salad of cabbage and speck
plum cake - crumbly cake base with lemon peel and a few ground nuts (hazelnuts?), with contrasting sharp plums on the top
Patscheiderhof was slightly bigger: more covers, seemed to have at least two people in the kitchen, several waitresses, and a slightly more ambitious menu to go with it, both in terms of length and cooking. Apart from a couple of pasta dishes on the menu, we could almost have been eating in Austria. Dishes we didn't have included sauerbraten and zweibelbraten. We ate:
soup with a "spleen sandwich" that had been cut into strips and fried - superior stock, generous croutons, would never have guess it was spleen if I hadn't known
ravioli con fungi porcini - only dud dish of the night. The pasta was very thick and fluffy. There were a few very tasty strips of porcini on top of the pasta, but the filling tasted like ordinary mushrooms, not porcini.
braised beef cheek - really tender, in a lovely sauce, with fluffy canederli alongside
tafelspitz - done in a good but light stock, with a sauce of pasley, oil, vinegar and a hint of garlic. A beautiful pairing.
hazelnut semifreddo - as it should be
poppy seed cake - nutty and green with ground pistachios, it also tasted like they had added a slug of their homemade walnut liquor. Bitter from the poppy seeds, but also sweet, slightly alcoholic, and moist. Absolutely fantastic
There is not much to chose between the two restaurants. My boyfriend preferred Signaterhof because the only directly comparable dish we had (the ravioli) were significantly better at Signaterhof. I preferred Patscheiderhof because it has a slightly nicer terrace, a more ambitious menu, and because the desserts were better.
re: jen kalb
Apparently it is on the menu. We found out about the walnut liquor because I wanted to know what the strange fruit tree in the garden was, and the waitress said that it was walnuts and they made liquor from the fruit. She also said that it was on the menu but I didn't pursue it because she described it as being like an amaro and I'm not an amaro fan.
Patscheiderhof appeared to use quite a lot of home grown food; they also make their own sausage and speck. Both Patscheiderhof and Signaterhof pride themselves in serving home made and/ or carefully sourced food.