BIG, BIG, BIG, fan of the perfect prep machine! My DH hates junk and clutter in the kitchen but he loves the prep machine (I persuaded him it was a good investment and when I reminded him that we have a coffee machine behind it that hasn't been used in three years, he relented!)
I found it a hassle either making up bottles and storing in the fridge to reheat at 11pm, 1am, 3am, 5am and so forth! (admittedly, told not to do this but my HV is old school and works on the understanding "it didn't do 'us' any harm!"). Both mine 'had this system' and neither ill from it or scalded. My DC2 moved to the prep machine at 6 weeks of age.
She is 8 months old and it is so easy to use my 3 year old actually makes her bottles (I shake them and supervise due to hot water being administered) but it takes less than 2 minutes to make a 6oz bottle. And at the un-Godly hours, it is a time saver.
I use aptamil first too. Midwives actually recommended it in hospital when my DC1 needed formula as i wasn't able to provide milk for him and his sugar levels dropped. They are all strictly regulated and yes C&G is much the same as aptamil but if you look and compare the nutritional info carefully, there are tiny differences. SMA (I got this on advice of my mother. Why, I have no idea considering she said SMA disagreed with me and I was put on Oyster milk or something like that!) disagreed with my DC1 so I moved onto Aptamil after breastfeeding was proving difficult at one month of age.
I too decided with DC2 that breastfeeding was to be done in hospital (easier) and this time would stop when I felt like it. It hasn't done her any harm. She's a healthy 8 month old gaining weight along her centile, only a few colds to speak of, no temp spikes or tummy bugs to speak of and no allergies either.