Flexible Dual-TCP/UDP Streaming Protocol with Adaptive Bitstream Prioritization (FDSP with Adaptive-BP) is a new method for streaming H.264-encoded High-definition (HD) video over WLANs. Traditionally, video streaming is done either using Transmission Control Protocol (TCP) or User Datagram Protocol (UDP) protocol, resulting in either rebuffering or packet loss respectively. While FDSP-based streaming addresses these issues, it experiences a new set of problems as it incurs both packet loss and re- buffering. This makes the actual Quality of Experience (QoE) delivered to end-users one of the key criteria in the Adaptive-BP selection process. As such, this paper presents an analysis of the subjective impact of both packet loss and rebuffering on video streaming quality as perceived by the end-user. Our QoE study focuses on identifying the threshold limits of both packet loss and rebuffering for the different Mean Opinion Score (MOS) ranges, which can then be applied to the Adaptive-BP algorithm to improve the end-user QoE for FDSP-streamed videos.