I have had mixed feelings about cc - I too feel really guilty about sending DD1, in part because she has been super clingy since about 20months and drop offs have been a nightmare. However she started 2 days a week at 9 months and was completely fine until that age. I went back to work fulltime when she was 2 - we had a combo of 3 days cc, 1 day mum or dad and 1 day grandparents and in hindsight this was too much for her.
The benefits have been huge related to her language and numeracy (not so great in the swearing/killing/guns/you are not my best friend department - however I guess this was always going to happen). Also toilet training and exposure to different songs/activities/food - it has opened her eyes and ours.
I also find it distracting and have trouble shutting off when at work but am getting better at it, well I was...I have been on ML with DD2 and am returning next week.
I work a long day so that also is a difficult thing for the kids - they get dropped off at 7.30am and picked up at 5.30pm, so that may be a consideration for you.
Overall the centre I have used has had fabulous staff who have treated my DD as extended family. They also do a wide range of craft activities that I have no chance of replicating. I could not speak more highly of them - I think it is really important to find somewhere that you are happy with and that will suit your needs. Good luck!