If one name stands out in the bond world, it's Bill Gross. He has a sterling reputation for making timely macroeconomic calls, including sidestepping some of the worst of the financial crisis by astutely avoiding the subprime mortgage market. Thanks to Gross's incredible investment results, and an overall rush to bonds by fearful investors, more and more money is finding its way into his fund's coffers. But can the bond guru keep up his winning streak?

Too big for its britches?
Gross's flagship PIMCO Total Return Fund (PTTAX) is a monster. With more than $234 billion in assets, it is the single largest mutual fund in existence, surpassing the previous leader, American Funds Growth Funds of America (AGTHX), with its "mere" $148 billion asset load. It's easy to see why the Total Return Fund is so popular -- it outranks 96% of all of its intermediate-term bond fund competitors over the past 15 years, and clocks in with an annualized 7.3% return in that time. But people are starting to wonder whether the fund is getting too big, and whether Gross will be able to duplicate his past results.

One thing is fairly certain: Bond returns in the future likely won't match the returns of recent years. Given where we are in the bond market cycle, amid historically low interest rates that have nowhere to go but up, there's a pretty good chance that the investors now stuffing all their money in the perceived safety of bond funds will be disappointed. So it will help if investors can moderate their expectations for future returns across the bond asset class.

As far as PIMCO Total Return's prospects, the fund is undoubtedly a behemoth. And while Gross and his team will face increasing pressures to invest their burgeoning asset load, I don't foresee too many problems for the fund right now. The universe of available debt securities is still growing faster than the fund itself, so supply shouldn't be an issue. However, investors may want a more nimble or flexible bond fund. Fortunately, Gross manages two other equally successful but less publicized funds. Both are even cheaper than PIMCO Total Return, and neither comes with its onerous front-end load.

Gross at a discount
Managers PIMCO Bond (MBDFX) has been sub-advised by Bill Gross since early 1994, and sports a modest $1.3 billion in assets. The fund comes with a price tag of just 0.59%, compared to 0.90% for PIMCO Total Return. However, Managers PIMCO Bond is run in the same style as its larger counterpart, with allocations to government, mortgage, corporate, and foreign bonds. While U.S. Treasuries make up the largest bond allocation, corporate issues from firms such as Citigroup (NYSE: C) and biotech Amgen (Nasdaq: AMGN) also contribute to nearly one-quarter of fund assets.

The fund has actually just edged out PIMCO Total Return in the past 15 years, with a 7.5% annualized return, versus 7.3% for Total Return. If you're looking for a more agile take on Bill Gross's abilities, Managers PIMCO Bond is a first-rate choice.

Likewise, Harbor Bond Fund (HABDX) is another PIMCO Total Return clone, sub-advised by Bill Gross since its 1987 inception. This fund offers a low $1,000 investment minimum, an annual expense ratio of 0.60%, and a 7.4% annualized return over the past decade and a half. Bond allocations here look fairly similar to Total Return and Managers PIMCO Bond, with a high Treasury allocation and exposure to mortgage and foreign bonds. Corporate issues from Oracle (Nasdaq: ORCL) and AT&T (NYSE: T) also make an appearance in the portfolio, based on Gross's interest rate and sector analysis for bonds that should do well in the low-yielding "new normal" environment. Thanks to its low costs and Gross's expert oversight, Harbor Bond would make an excellent anchor for any investor's bond portfolio.

On the cheap
Of course, if paying for active bond management just isn't your thing, you're better off going with inexpensive exchange-traded funds. Two of the best in this space are iShares Barclays Aggregate Bond Index (NYSE: AGG) and Vanguard Total Bond Market ETF (NYSE: BND). Both funds offer broad bond market coverage for a low, low price, so it's hard to go wrong here.

Ultimately, I'm not worried about Bill Gross losing his touch, or being buried under an unmanageable asset load, just yet. But investors should be aware that the bond returns of the past decade or so are unlikely to repeat themselves in coming years. Gross is still one of the best in the bond business, but before buying PIMCO Total Return, be sure to consider one of the other, less expensive bond options that Gross manages. Getting the same professional management for a cheaper price is a win-win situation for bond investors of all stripes.

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Amanda Kish is the Fool's resident fund advisor for the Rule Your Retirement investment newsletter. Amanda owns shares of Managers PIMCO Bond and iShares Barclays Aggregate Bond Index. The Fool owns shares of Oracle and Vanguard Total Bond Market ETF. The Fool has a disclosure policy.