Despite the low price tag, the Monoprice 4x1 switcher did about average in our performance tests. The switcher's HDMI ports are certified at "only" version 1.2 of the standard (not the newer 1.3); however, we had no problem passing 1080p/24 video with DTS-HD Master Audio soundtracks in bit-stream format. While the Monoprice 4x1 switcher has a newer firmware revision than the 5x1 switcher, we found it to perform a little worse in two areas: speed and long cable runs. While the 5x1 switcher averaged around 3 seconds to switch between inputs, the 4x1 switcher averaged a considerably longer 7 seconds. We also didn't have any luck with the 4x1 switcher when we hooked it up to the our extralong 65ft HDMI cable, so anyone planning to use long cable runs should look elsewhere.
A caveat to all HDMI switchers--and products with HDMI ports in general--is that we've found frustrating compatibility issues in a variety of scenarios. An HDMI switcher may work perfectly well in one setup and then not work in another setup because of a different combination of home-theater components. Because of this, we recommend buying a switcher from a retailer with a solid return policy, as it's impossible to know if it will work flawlessly in your setup ahead of time.
Overall, despite the slow switching speeds and difficulty with long cable runs, the Monoprice 4x1 switcher delivers a solid functionality for the budget price of $44. While we would be inclined to give the Monoprice 4x1 switcher a strong recommendation at its price, that's tough to do when Monoprice offers a superior, only slightly more expensive 5x1 switcher ($50 at the time of this review). For just 6 extra bucks you get another HDMI input, faster switcher speeds, and better compatibility with long cable runs. Both Monoprice switchers offer an excellent value, but we like the 5x1 switcher a bit more.