Financial advisers rate Vanguard the No. 1 provider of exchange-traded funds, rating the company high on nine out of 10 metrics, Cogent Research found, in its 2010 Adviser BrandscapeBarclays iShares’ 20%.  NPS is a standardized loyalty metric developed by Bain & Co. and deployed across many industries, according to Cogent. survey of 1,560 advisers. Vanguard rated a Net Promoter Score (NPS) of 33%, compared to market share leader

Among the top five ETF investment advisors, Vanguard was the only one to achieve gains in 2010. In 2009, 37% of producers said they invest clients’ money in Vanguard ETF, and in 2010, that rose to usage of 42%. By comparison, 90% of producers placed clients’ money in Barclays ETFs in 2009. This year, that figure edged down to 87%.

Cogent also found that the average amount of assets each adviser manages in Vanguard ETFs more than doubled, from $2.3 million in 2009 to $5.5 million in 2010. For iShares, the AUM per adviser is $5.7 million.

“Obviously, in terms of penetration, they have a long way to go to catch iShares, but right now, the momentum is clearly with Vanguard,” said Cogent Principal John Meunier. Driving adviser interest in Vanguard ETFs, Meunier said, is customer service.

Vanguard also offers some of the lowest-cost index and exchange-traded funds on the market, which appears to have driven the ETF price wars among providers and brokers alike.

Meanwhile, the Cogent research also shows that advisers’ usage of State Street Corp.’s SPDR’s ETFs remained flat at 55%, while Invesco PowerShares moved from 53% in 2009 to 49% in 2010. ProShares also lost some momentum, from usage of 34% last year, to 30%.

The report also found a marked increase in ETF popularity, with 60% of advisers selling ETFs to their clients, up from 55% in 2009 and 46% in 2007. Usage is up among all channels, and highest among national advisers and RIAs (74%).  Among standard mutual funds, few advisers anticipate increasing their usage. In fact, they anticipate that their future allocations to mutual funds will remain flat at portfolio allocations of 35%.