The generation of microvascular maps using optical coherence tomography (OCT) angiography (OCTA) is attractive as it does not require exogenous contrast agents. Low-cost OCT equipment typically provides only the final processed image, limiting the use to intensity-based methods. The present study compares intensity-based methods for acquiring microvascular maps using OCTA. We evaluated Histogram Flow Mapping, Short-Time Series, Correlation Mapping, Speckle Variance (SV), Optimized Speckle Variance, and Improved Speckle Contrast using a microfluidic phantom. Performance was assessed by signal-to-noise ratio (SNR), contrast, contrast-to-noise ratio (CNR), and processing time. Among the methods, SV emerged as the most efficient. While exhibiting the lowest SNR, SV achieved the highest contrast and comparable CNR to others. Notably, SV boasted significantly faster processing times. This is crucial for large datasets encountered in 3D imaging. While focusing on four key metrics, we acknowledge the potential relevance of others for specific applications. However, for scenarios with limited OCT images where the focus is on the processed structural image, the SV-OCT method remains a compelling choice due to its high contrast, comparable CNR, and superior processing speed.