The increasing availability of Head-mounted displays (HMDs) has prompted extensive research to improve gaze interaction in Virtual Reality (VR). Selecting the most suitable HMD for research and design remains a challenge, with gaze accuracy and precision playing crucial roles in determining the efficacy of eye-tracking measurements. This paper compares gaze accuracy, precision, and tracking area across four VR headsets: Tobii Pro, Vive Pro Eye, Vive Focus 3, and Meta Quest Pro (in both stand-alone and tethered modes). All VR headsets exhibit accurate performance in the central region but face challenges in the peripheral area (> 15 degrees), requiring careful consideration for research applications. Variations in sample-to-sample distance and dispersion among headsets impact fixation quality and gaze gestures, influencing the headset choice for specific research needs. Our findings provide valuable insights for researchers and designers, guiding decisions in selecting VR headsets for gaze interaction and enhancing user experiences across diverse applications.