The performance of TCP Vegas degrades significantly when used over networks with a large bandwidth delay product or when the receiver implements delayed acknowledgments. Three sender-side modifications have previously been proposed, aiming to overcome these problems. We have demonstrated that these modifications, collectively known as TCP New Vegas, provide significant performance gains (in excess of 300% in certain cases) whilst maintaining the primary benefits provided by TCP Vegas? design. This paper details further research undertaken to validate these modifications and to evaluate the performance of TCP New Vegas when used over networks with limited buffers, multiple hops, error-prone links and competing flows.