It's always a worry when they get a new teacher esp if it is one you havent heard favourable things about.
I am a firm believer in waiting to see if fears are justified.......not much you can do at this stage anyway so just see how DS gets on with her - he may love her and all your fears may be unfounded. It's not worth getting your knickers in a twist about it just yet! Presumably if she was hauled away from year 1 and is now back she is up to speed with the teaching aspect ........ she may surprise you!
YANBU to be worried but you need to just suck it and see, so to speak.
Altinkum - we have a year 4 teacher who has a reputation for being...well shit!! Anyway, there was a big uproar from the parents who went into his class last year - people were complaining, saying they didnt want him etc etc...you know what??? They love him and he has been ace.........
Am sure (fingers crosssed) it will be the same for you! Who knows, maybe had had a difficult class this year.....I dunno......must make a difference
am sure all will be ok, are you szure that there were complaints no playground gossip? my ds1 has just finished yr 1 and ds2 about to start they will cope (although ds1 would have happily stayed in reception til he left, as the toys are cool )