Yes, karen, I have a short experience with this geranium this year.
It is of French origin, by the way, and was named after the wife of the breeder, Sandrine Delabroye (see link below, bottom of the main page). Thierry Delabroye is a terrible perennial-holic, and their nursery is definitely one of my favs in France!
Geranium 'Sandrine' is very close to the better known 'Dragon Heart'. It has superb lime-green young foliage when it emerges, and again if you cut it back as I had to do it a month ago (after a cat's unexpected digging work...).
A nice contrast with the very large magenta flowers (especially the earliest ones, over one inch wide!).
It does ramble a lot through the neighbouring plants : mine was about 4 feet large (its first year !!!) after 3 months only!
But I have so far no experience about its behaviour in winter...(I'm zone 7b USDA)
Mine is in half shade in a fairly clayish soil, a never-dry location..which might be a problem next winter if the soil doesn't drain enough...Time will tell!
Hope this helps
{{gwi:826338}}.{{gwi:826339}}
Zephirine

Here is a link that might be useful: pepinieres delabroye

Thanks Zephirine!! This one is definitely on my list!!

--Karen