It was looked on CBC not long ago and here is their findings.
http://www.cbc.ca/news/background/customer-service/results.html
Rank Company Name Category Score
1 Sears Home Repair Retail 90.9
2 Bank of Nova Scotia Visa Credit 90.3
3 Aliant Telephone 86.8
4 Fidelity Investments Brokerage 86.6
4 TD Waterhouse Brokerage 86.6
5 Flight Centre Travel 85.7
6 Cogeco Cable Cable 84.6
7 RBC Visa Credit 84.2
8 Shaw Cable 83.9
9 Globe and Mail Media 83.2
10 American Express Credit 80.5
11 SaskTel Telephone 80.0
12 Sears Catalogue Retail 78.3
13 Canadian Tire Retail 75.2
14 Microsoft Computer 75.1
15 CBC Media 74.8
15 TD Canada Trust Visa Credit 74.8
16 Aeroplan Travel 73.6
16 Telus Telephone 73.6
17 Bell Sympatico Computer 72.8
18 Rogers Wireless Telephone 72.3
19 WestJet Travel 70.2
20 CIBC Visa Credit 67.0
21 Chapters Indigo Retail 65.7
22 Expedia.ca Travel 64.4
23 Air Canada Travel 64.2
24 Rogers Cable Cable 64.0
25 Dell Computer Computer 60.4
25 National Student Loans Government 60.4
26 MTS Allstream Telephone 58.0
27 Rogers Yahoo Internet Computer 57.7
28 National Post Media 57.1
29 Telus Internet Computer 56.2
30 BMO Bank of Montreal Mastercard Credit 53.2
31 Bell Mobility/Home Phone Telephone 52.7
32 Sun Life Insurance 51.3
33 Great West Life Insurance 50.0
34 Canada Revenue Agency Government 49.0
35 HBC Retail 48.3
36 President's Choice Financial Mastercard Credit 22.8