I'm sure you'll be very happy with the wxr but what was the reason for getting the wsd81 instead of a wxp80 iron and stand too use with your new wxr3 station?
Good question.
It doesn't make sense on the face of it, doesn't it?
The main reason for a separate single channel station is for transportability. I can pop the WSD in my backpack and take it to community tech/hack meetups, uni and (depending on the sort of people I'm contracted to work with) work.
I sometimes need to move the iron to the workpiece and it would be more of a faff shifting a 3 channel station.
It's the cheapest option for a good station, the tips are a bit cheaper and I can borrow/ swap tips with other community tech group users. I can get tips retail locally.
Talking of tip-swapping it cools quick enough when de-energised to not make tip swapping a pain. That's not to say it loses temperature quickly when soldering. It doesn't. I tested by removing heatsinks from a PTH board I trousered from a television set dumped in the street for waste collection. No temperature recovery problems at all. My background is telecommunications so if I do board level work I'm going to meet ground planes, big ground planes.
As to the choice of station ... I couldn't justify £500+ on a single channel WX station as a 'traveller'.
I got a good deal on the WSD81i station.
For on the lab bench I don't always need to fire up on all channels when it's a simple job such as swapping a battery pack.
There's also availability. If I need the send the WXR away to be repaired I don't want all my eggs in the same basket so with a separate soldering station I've still got something with which to do through hole work while it is being repaired.
I've spent weeks trying to justify buying one station let alone two.
The 3 channel decision was a no-brainer (I need hot air, I need desolder iron) but that didn't stop me labouring over the decision to invest in one for over a month. l'm a bit, err, 'prudent' to understate and hummed and hawed for weeks ("will this help me earn?", "do I really need it?", "does my usage justify the cost?")with decisions to invest in other equipment that gets daily or near-daily usage (Flukes, battery drill, new computer, flashlights, hand tools ....). I spent less on the WSD station and component costs than the cost of replacing the items I repaired with it on the first day of ownership, so it's kind of paid for.
It might take a matter of weeks for payback on the WXR but only because I need to get in practice again.
That's my decision process laid bare, I think (yeah it's probably irrational and replete with inconsistencies)
I wish I'd invested in my own station earlier.