Sunrise sucks massively. Just google for Sunrise and Kundendienst. I've lived in Switzerland for 30 years and have never been with a company that treats their own customers as crappy as Sunrise.
You will find everyone has different views on the providers. We have been with both swisscom and UPC and swisscom were really poor connections abot 3 years ago. Since being on cablecom the connection is brilliant, service is fine and for 75CHF we have TV + internet + phone in CH which is a very good deal.
Have usually have had very good service although hardly ever need to use them and in over 3 years we have not had any regrets. swisscom or Bluewin were shocking 3 years ago when the telephone ringing always cut your internet off and froze the TV including when you hung up the phone
I'm with TalkTalk with one bill for everything- fixed line, mobile and internet - and it is always under 100 Fr. a month including all our mobile calls (no monthly abo charges), since most of our calls + SMS are to each other and those are free. 100MB of mobile data is also included. They also have their contracts and detailed billing in English.
Cablecom still has a somehow bad image from the past. Don't understand it because I once was a happy Cablecom/Internet user. And I just switched from Swisscom Phone/Internet to Cablecom again. Their basic internet is much faster at a lower price.
I had Cablecom for a few years-their hardware for digital TV was just bad bad bad. At first problems with the infra red remote control. This was a common problem which maybe they have fixed now.They replaced my modem at least 4 times and still there was problems. Maybe they have improved-I have had Swisscom for a couple of years now and never problems.