Consumers who want to avoid a dispute with their financial services provider should think carefully about doing business with GE Money, Macquarie Bank or, among the big banks, National Australia Bank. They are all prominent among financial institutions with poor dispute records, according to the latest Financial Ombudsman Service comparative tables.Rather than publish the raw number of disputes for each financial institution, FOS provides a measure called "chance of a dispute coming to FOS", which shows the number of disputes relative to the size of the business.For example, the likelihood that home loan borrowers will find themselves taking a dispute with their lender to the Financial Ombudsman Service is 60.5 in 100,000. That is, FOS's complaints file for 2012/13 shows that for every 100,000 home loan customers the median number of disputes is 60.5.However, for Macquarie Bank customers, the likelihood is 285.5 in 100,000 - almost five times the median.Other housing finance providers whose customers are more likely to complain are Over Fifty Seniors Equity Release, which recorded 252.5 complaints per 100,000 customers, GE Personal Finance (244.1), RHG Mortgage Corp (176.5) Rams Financial Group (141.1), Bank of Queensland (105.9) and NAB (74.7).The GE business referred to here is personal loans secured by residential property, not the old GE mortgage book, which was sold to the Pepper Group.Lenders with a score below the median included Westpac, Citibank, CUA, HSBC, ME Bank and AMP Bank.When it comes to credit cards, the overall likelihood that a customer would take a dispute to FOS was much lower, at 18 in 100,000. For Macquarie Bank credit card customers, the likelihood was 50.3 in 100,000. Other credit card issuers with high dispute scores include HSBC (49.7), Citibank (39.7), National Australia Bank (22.9) and GE (21.6).In the deposits and payments category, the likelihood of a dispute was 4.1 in 100,000.In this product category, MyState Financial had a blow-out, with a dispute score of 33.5 in 100,000. Others with high scores include Rams (19.8), HSBC (13.5), and National Australia Bank (7.8).In the consumer lending market, which includes leases, the likelihood of a dispute was 37.9 out of 100,000.GE Automotive Financial Services attracted the most complaints on FOS's comparative measure, with a dispute score of 130.2 in 100,000. Other consumer lenders with high scores included Mercedes-Benz Financial Services (118.4), St George Motor Finance (95.7), Capital Finance (91.5), National Australia Bank (86.6) and Bendigo and Adelaide Bank (84.5).