From what I know of her, she seems very good. We bought a pony that she originally owned and he turned out to be a super-star - we went to see her and she was thrilled that a pony she had bought as a 4 yr old had turned out well.
Yes I know of Astrid, went to look at one of hers before I bought my current horse. I know a few people who have bought their horses from her and are extremely happy with them. She always has some stunning horses in.
I know Astrid quite well (she's very local to us) and we've bought a couple of horses from her, as well as knowing lots of other people round here who've bought from her.
One of the ones we bought as a 3yo last year was very green and just backed. He was a bit much for us to be honest (limited time/facilities) so we sent him away for professional schooling. He recently won the 4yo International Potential Dressage Horse at Somerford Park Premier League and will be at the Nationals next month. The other one we bought wasn't even handled - straight from a field in Holland. He was a stunning horse and once he realised human beings weren't scary he was the sweetest of natures and like a lamb to handle. He was very sharp to ride though and slow to mature - like a lot of warmbloods.
So I would definitely highly recommend her - the horses she picks and brings over are all stunning and you only have to read H&H each week to see how well horses she's supplied do. The only thing I would say is that if you buy a 3 or 4yo from her and she says its backed then it really is just that. Astrid backs them quickly (walk/trot and stagger are her words), they don't get out hacking (yard is on a very busy road about 50 yards from the motorway roundabout) and she doesn't take them to shows (as far as I know anyway) - so when you get them home they are still very green and babyish and some of the groundwork may be slightly lacking. However Astrid's quick turnaround is why she doesn't put silly price tags on her horses.
Definitely worth a visit and its unlikely you won't fall in love with at least a handful of them.
I drive past 4 times a day! Yes you get a great view of her outdoor school from the M65 motorway... it can be quite distracting if something nice is being schooled whilst you drive past
Yes she has an excellent reputation, my cousin used to ride her jumping horses. She does pick them for performance and trainability so you should get a good one, whatever you decide.