I bought a Uniden DFR9 from Costco. $260. Returns are easy if you find you don't like it.
Waze is a wonderful app...but that's all it is. It works great if you have cell phone coverage —
and are in a built-up area where others take the trouble to send in LEO reports. If you're out in a Podunk area with a population of 50 souls and 1 LEO...it is worthless. If you're out where there's no cell phone coverage...it is worthless.
I bought mine because there are two local roads that are potential trouble spots for me. The main road to my place has a speed limit of 30 mph, but I've been known to go slightly above that. About once a year, the LEOs set up a radar trap to catch the drivers going 55-60 mph...the road parallels I-5 and many drivers go on this road to bypass the traffic.
The other road is on the way to church. Speed limit is 35 mph, but it has five lanes and begs to be driven at 45-50 mph. They do get radar traps out there. Even though I pretty much pace the traffic...I don't want to be the one they pick out of the crowd to talk to.
And then there's a friend of mine who is a model motorcycle rider in town and in traffic. But when he gets out in the countryside, he likes to "make progress". He's at the front, and I'm usually at the rear. I figure that I can get some advance warning that an LEO is in the area as the cop lights him up.
As for riding in the rain, I simply store mine in the garage. To me, it is just a "toy". I don't ride like I have a license to speed with it. But it does give me some peace of mind if I'm in the middle of nowhere and I'm going at a comfortable pace.
For those who can't work out using the audio feed, Marc Parnes makes a Visual Alert for radar detectors.
http://www.marcparnes.com/Visual_Alert.htm The cost is very reasonable and mine works great.
Chris