So far OEM blades seem pretty good, on my other car I use Bosch marathons which have been superseded with something very similar (can't remember the new name). These wipers were excellent on my car, but reading up on them they seemed to have a fairly mixed review. I am not sure if there is an XC60 version.

As far as windscreen treatments - it's hard to source - but I use a Japanese product called "ultra glaco" by soft99. It may be marketing hype, but the Japanese sell lots of versions of rain repellant with various speed and or durability factors. I have found it to be much better than rain-x. Having said that rain-x is pretty much the only product readily available if I can't get glaco.

I don't use the rain x windshield washer product, it tends to destroy the wipers.

 

I had the dealer replace the inserts with Volvo ones last winter, as they were covered by S&S. I haven't been that impressed with the OEM blades, both sets. The original ones I thought maybe dried out because of the summer. I notice the initial swipe to the left, everything is great, but the downward swipe - smears. Do you notice this at all on your car? We are in the same region too.

I had Bosch Icon's on my previous car, and they were fantastic - didn't replace them for over a year. Well worth the price, held up during the bad snow storm and rain. I too am looking to get better blades this time of year.

 

I have not had an issue with the OEM Volvo wipers. I have had them replaced once under S&S. By the way, the OEM wipers appear to be Bosch Aerotwin which is a Bosch style not commonly sold in the USA.
IPDUSA has PIAA SI-TECH silicone rubber wiper blades, though the are more expensive than the OEM.

 

I'm still on stock wipers and have had no issues so I can't help there.

As for treatments, I've used Rain-X and Aquapel (sourced from Amazon.com). Rain-x is slightly better than Aquapel when it's initially applied but Aquapel last significantly longer. I find Rain-X to be okay until I have to use my wipers then it seems like it looses 30% effectiveness with the first swipe of the wipers. Aquapel is much more consistent and durable. It's all I use these days.

Link to Amazon:
Amazon-Aquapel

It's significantly more expensive than Rain-X but it's nice to only have to apply once a year.

 

Whatever came on my CPO was a silicone variety and that's what I'm using. Got some brand for the wife's Fusion as well.

Window treatment is Diamon Fusion. The dealer had a special on it and reapplies it for free.

http://www.dfisolutions.com/products/diamon-fusion/

 

Haven't purchased wipers for our XC60 yet (still under S&S) but if you're a Costco member they have Goodyear Assurance wipers that can't be beat for $4.99 each. They are $15-$20 each everywhere else.

 

Couldn't agree more. I replace mine with the Assurance wipers when I swap my Summer tires for winter tires and vice versa. Probably overkill but we use straight de-icing fluid here so the fluid often is harsh on the rubber.

As for windshield treatment I had aquapel installed and love it! Driving on the highway in decent rain I often don't even need the wipers on.

 

No issues with wipers or need for treatments on either XC60 after about one year so far in always rainy Seattle. My wife's XC60 has the heated windshield which causes a lot of annoying mesh wire glare and distraction on dark wet nights though. Not sure there is anything to be done to mitigate that problem!