I've always been very happy with my VMG8924-B10A. I have tried a lot of other modem/routers over the years and the Zyxel is always the one that ends up back on my line. The main reason for this is that I've struggled to find anything else that performs as well on the modem side. This is a very personal thing as all lines differ in which modem they like best, but you certainly should get decent results on pretty much any line.
On the router side of things I like the interface, and although it isn't the most user friendly around it's certainly not bad (plenty of help available on here too!).
The wireless side is quite adequate - not the best,but certainly a long way from the worst. Again how well it works for you will depend on the size and build of your house as well as the router's location.
As you say, they are freely available for sensible prices so I'd say go for it.