An analysis comparing the Vanguard Long-Term Treasury ETF (VGLT) and the iShares 20+ Year Treasury Bond ETF (TLT) noted that VGLT's expense ratio is significantly lower than TLT's (0.03% vs. 0.15%, respectively). VGLT primarily invests in U.S. Treasury bonds with maturities between 10 and 25 years, while TLT focuses on ultra-long-term Treasury bonds with maturities exceeding 20 years. Although their yields are similar (VGLT at 4.75% and TLT at 4.72%), the analysis suggests that VGLT might be a better choice for most investors due to its lower cost and smaller volatility.