Here is something I posted on the Atlas forum:
OPERATING REPORT
Last night I had the opportunity to run these PWRS Saskatchewan grain cars in a unit grain train with Intermountain cylindrical hoppers. I must regrettably admit that I was very upset and disappointed with the way these cars performed on the layout. First, a disclaimer: the layout is not my own, it is the work of my friend Don Meeker who is an NMRA master model railroader - his trackwork is flawless, and I've never had any problems with derailments while running on his beautiful mountain-themed layout. Even the old Athearn Genesis cars with semi-scale wheels have no problems negotiating the layout's trackwork.
The PWRS Saskatchewan cars, to put it bluntly, were an operational nightmare. (Just to remind everyone I am not a default "PWRS Hater", I remind you that I am the one who created this post proclaiming the cars' beauty and attention to detail). However, that's where the quality of these cars end: the cars were equipped with "narrower than semi-scale wheels" (traditional semi-scales, as I've stated, posed no problems on the layout on which they were test run), but the PWRS wheels are even *thinner* than the semi-scale wheels that come with Athearn Genesis cars, for example.
At every curve, and every turnout, the Saskatchewan cars would be derailing while the Intermountain cars solidly stayed on the track. On sections of track that we checked multiple times with an NMRA guage, the wheels on the car would simply "fall between" the rails and derail... the wheel treads on the Saskatchewan cars are simply too narrow to expect reliable operation; they are even narrower than traditional semi-scale wheels that you can buy from Intermountain or that came with the Athearn Genesis cars. I'm all for prototypical accuracy, but when it comes to wheel treads, there is a balancing act between meeting prototype standards and achieving reliable operation on an HO scale layout.
While everyone was astonished with how beautiful my string of 13 Saskatchewan cars looked, their positive impressions of the PWRS cars were quickly diminished by non-stop derailments. I was looking forward to showing these cars off, but I quickly became embarrassed with how poorly they tracked.
Last night, after a night of frustration and disappointment, I decided to insert a
standard tread Intermountain wheel into the truck of a PWRS car. I thought it would roll just as freely, being how similar these cars are to Intermountain in the first place. Well, I was wrong... the standard Intermountain wheel had so much friction inside of the truck, it would barely roll. To get the standard Intermountain wheel to free-roll within the PWRS truck, I had to use my "reamer" tool to provide extra clearance for the axle. Even after reaming the truck, the Intermountain wheel was still not as free-rolling as the PWRS wheels which I'm sure were designed specifically for that truck. The picture below illustrates three wheelsets: an Athearn Genesis "semi scale" wheel, the wheel that came with the PWRS cars, and a standard tread-width Intermountain wheel inserted into the PWRS truck. As the picture shows, the treads on the PWRS wheel are even *narrower* than the treads on your typical semi-scale wheel (itself which was known to cause derailment issues on many layouts... can you imagine an even narrower tread wheel?)
The wheelsets that come with the PWRS cars are simply unacceptable and prevent the reliable operation of these cars. These are beautiful, well-crafted cars, no doubt about it... however, the wheels they come with are utterly useless and mar the entire project ,taking the wind out of what could have been one of the most exciting product releases of the year. I am very upset that PWRS would allow these cars to be released with wheelsets even narrower than traditional semi-scale wheels; they should have anticipated the operational problems they would have caused.
SO, before I go ahead and ream 25 more trucks, I would like to find out what PWRS' intentions are on providing us with a standard-tread wheelset so that we can actually OPERATE these cars, as opposed to letting them collect dust on a shelf. For now, my PWRS cars will sit in their box and never see operational time again - they simply won't operate without derailing all the time!
Sadly, this will also likely be the last product I buy from PWRS unless they provide us with a standard-tread wheel to use. I have invested a significant amount of money into these 13 cars, and to say that I am disappointed with them right now is an understatement. It's a shame, too, since I was holding out so much hope for PWRS. They had so much promise as a manufacturer... 
