Thin, especially the Sprott funds.
The disadvantage they have is that their floats and daily volumes are deep enough to allow them to be used for momentum trading and shorting in arb plays, as compared to other bullion vehicles. They also pay no dividends, and redemptions for bullion are minimal.
The battering the miners have taken is remarkable. Some of them have attractive PE's and dividends that are catching my interest once again as long term holdings.
As a word of caution, relatively high dividend yields may be attractive but can also be a sign of other troubles depressing the stock price and inflating the yield, temporarily in some cases.
