My experience with City Chain is alright. My favourite is the Bugis Junction branch. I bought my casual watch S&T there and changed battery there. No problem. Good smile, good service, first battery change within 5 years of sale also free. The girl even put the watch back on my wrist for me, held my hand and asked me comfy or not, need to adjust the bracelet or not, also free.
Of course, can't compare with my formal watch Rolex, which has to be serviced at Tong Building. There nothing is free, cleaning already starts at S$200.