We tested the Zyxel PLA4211's against PLa4201's and Devolo's pass-through 500Mbps and 200Mbps adaptors using typical conditions in a house, transferring a file from one PC to another in separate rooms via a Gigabit router. We transferred a 500MB video file, recording the transfer speed in MB/sec.
Devolo 500Mbps Pass-through
Zyxel PLA4201 500Mbps
Devolo 200Mbps Pass-through
MB/sec - higher is better
While the results aren't earth-shattering, the fact the PLA4211 was able to add another 1.6MB/sec to the transfer speed of the PLA4201 is a welcome addition, essentially taking the bandwidth from 79Mbps to 92Mbps at its maximum of 11.5MB/sec. It's still pitiful compared to the 125MB/sec you'd likely see from CAT5 cable, but if you're mainly using it for the Internet rather than networking and the like, then 92Mbps should satisfy most people's needs and should cope happily with streaming HD content too.
The real speed daemon, though, is the Devolo 500Mbps pass-through kit, which managed a comparatively stonking 16.1MB/sec. Clearly, if you're the proud owner of 100Mbit broadband or plan on dishing out lots of data across your network, the Devolo 500Mbps is the way to go - it's nearly 30% faster in typical conditions. For some perspective, this would shave nearly ten minutes off the thirty minutes it would take the PLA4211's to transfer 20GB of data.
Click to enlarge
We shouldn't forget about price though. At just over £50, the PLA4211s are cheap for a dual 500Mbps set - Devolo's set that we tested retails for around £90 so you're paying a real premium for a few extra megabytes a second.
However, if you're not fussed about a pass-though adaptor, the Zyxel PLA4201's cost just £30 at the moment. They might only shift 10MB/sec but they're a third of the price of the Devolo 500Mbps kit, yet offer slightly less than two thirds of the speed. As an affordable pass-through adaptor, though, the PLA4211 isn't the fastest out there, but represents good value, especially if you'll just be using it to tap into the Internet.