I have an early model - the WR-1000i
• rx capabilities, software, and support
All excellent, although I think the software looks a little ugly
I had a fault occur during the warranty and they fixed it and shipped it back pronto. Mine has a BNC for antenna due to the limited space on the back of an internal card. Would have preferred N type but that's the way it goes. The spectrum scan comes in handy. You set the lower and upper limit, mode, bandwidth etc and start it. It sweeps with a graphical display to show signal strength. After the first sweep it also shows min, max and max minus min so you can see what's happening over time... helps to find frequencies that are not used often.
I bought the digital package as well, which was the original one they did back then. It's not very good on what it supports and it doesn't support much. They do a new version which is supposed to be a lot better. There are heaps of other extra packages as well, specialty digital modes etc. None of them are cheap.
• Linux or Windows, how does it handle
Windows. I don't have Linux on the PC that the device is in. I can think of a few improvements that would suit me, but it does what it supposed to. Being able to control it from other programs and over LAN is handy. I've even got a DOS app to control it. Dunno if they still supply or support that.
• What antennae both fixed and mobile would you recommend
Can't say for mobile... not sure what is truly wideband. My device is internal so unlikely to ever be mobile.
For base, get a Diamond VHF/UHF discone up high. I've never had one but that's always the answer from others. If you want to listen to HF or short wave then a separate antenna, probably a long wire, also up high and as long as you can get. The discone won't pull much in at low frequencies.
Like I said, it's an old model that isn't sold any more, but it is still supported with software updates. Any new models will likely have better software and features.