I have a CP 150C (now discontinued) which looks like a CP 155C. It is a nice compact unit which flush or surface mounts.
It does just what it says on the box. Since I found the "Sunlight" display setting, I can not fault it.
The joystick takes a bit of getting used to, but I now find it easier than a load of buttons.
It also carries a 3 year gaurantee and now has the added support of Mr Jon Brooks, who will no doubt be along soon.
"A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools" Douglas Adams