The funds in our "Magnificent Retirement Mutual Funds" list are some of the top-performing, best managed funds available. If you're already invested in them, congratulations! If you're not, don't worry - it's never too late to start getting the advantages of these outstanding funds for your retirement.The easiest, most reliable way to judge a mutual fund's quality over time is by analyzing its performance, diversification, and fees. Our Zacks Rank covers over 19,000 mutual funds has helped us identify three outstanding options that are perfect for any long-term investors' portfolios that is retirement-focused.Let's break down some of the mutual funds with the highest Zacks Rank and the lowest fees.Nationwide Growth R6 (MUIGX) has a 0.5% expense ratio and 0.45% management fee. MUIGX is a Large Cap Growth mutual fund, and these funds invest in many large U.S. firms that are projected to grow at a faster rate than their large-cap peers. With yearly returns of 11.97% over the last five years, this fund clearly wins.AllianzGI Convertible Fund P (ANCMX). Expense ratio: 0.7%. Management fee: 0.57%. ANCMX is categorized as a Convertible Bonds fund, and in the fixed income world, these funds are quite unique. These types of securities are a hybrid, meaning they have components of both fixed income and equity. This fund has managed to produce a robust 10.71% over the last five years.MFS Mid-Cap Growth Fund 529A (EAMCX) is an attractive large-cap allocation. EAMCX is a Mid Cap Growth mutual fund. Mid Cap Growth funds pick stocks--usually companies with a market cap between $2 billion and $10 billion--that demonstrate extensive growth opportunities for investors compared to their peers. EAMCX has an expense ratio of 1.07%, management fee of 0.69%, and annual returns of 12.24% over the past five years.There you have it. If your financial advisor had you put your money into any of our "Magnificent Retirement Mutual Funds," then they've got you covered. If not, you may need to talk.Do You Know the Top 9 Retirement Investing Mistakes?Investing in underperforming mutual funds is just one of the key errors that can derail your retirement plans.To learn more, read our just-released report: 9 Retirement Mistakes You Need to Avoid.This report can help you sidestep these costly mistakes and potentially achieve your retirement goals. Get Your FREE Guide Now Get Your Free (ANCMX): Fund Analysis Report Get Your Free (EAMCX): Fund Analysis Report Get Your Free (MUIGX): Fund Analysis Report To read this article on Zacks.com click here. Zacks Investment Research