Yes - I too recently took delivery of one of these wagons and I have to say I was somewhat disapointed when I compared them to some of the superb 'Peat' wagons that I had previously bought from the same manufacturer and the same dealer.
Here's a summary of the reply I gave to a fellow member on another forum when asked the reason why ........
The first thing I noticed when I unpacked the wagon was how rough it ran when I put it on a piece of track and it soon became evident that there were three main reasons for this.
1) - The wheels were not running true to the axles - there was both a radial excentricity and an axial wobble.
It appears that the design of these axles have been progressively downgraded over time - back in the days when the L & B 4 ton van first appeared the axles were of a triple diameter design - 5.0mm for the wheel locating land - 3.5 mm for the hub mounting - and 3.0 mm for the bearing section. In addition they had axial splines on the 3.5 mm section to give additional location for the wheel.
When the 'Peate' wagons came along, the axles were still of the triple diameter design, but the axial splines had been deleted. However, to compensate for the loss of the splines, the diameter of the hub mounting section had been increased from 3.5 mm to 4.3 mm diameter.
Now we come to the 'I of M' wagon axles which have been reduced to a simple two diameter design. The diameter of the hub mounting section has been reduced to be the same as that of the bearing section - i.e. 3.0 mm - which doesn't appear to be adequate considering that the 'I of M' wheels are bigger than the 'Peate' ones.
2) - All 4 wheels don't contact the track at the same time due to perhaps the most significant difference between the two designs.
On the 'Peate' wagons the W-irons have a flange running along the top edge which provides positive location up against the underside of the wagon floor. - On the 'I of M's there is no such flange - the irons are completely flat and so there is no positive location other than two M2 X 5mm self tapping screws which are a loose clearance fit in the irons.
Curiously - there are reinforcing pads moulded or glued to the floor in way of the irons, but the irons are completely clear of these pads by between 0.7 to 2.0mm
Unlike the 'Peat' wagons where the W-irons, axle boxes and springs are all cast as a single unit - the 'I of M' axle boxes actually slide in the irons as though it was originally intended that the wheels should be sprung. The big cut outs in the replica springs also look as though they were intended to accomodate real springs at some point.
I think the point here is that - if you are going to delete the locating flanges, then you need springing to compensate for the differences in height - and if you are going to delete the springing, then you need the flanges to positively locate the W-irons. However, if you delete both the flanges and the springing, then there is not much chance of keeping all 4 wheels in contact with the track at the same time.
3) - The 'Peat' wheels appear to be fully machined stainless steel - whereas, the 'I of M' wheels appear to be completely un-machined white metal castings. This cast finish is of a high quality but the imperfections on the rolling surface of the tire are just too big to allow smooth running - these deffects are difficult to see because the whole wheel, including the actual rolling surface in contact with the rail is covered in black paint.
There are a number of other points where the 'Peat' wagons are superior to the 'I of M's'
- Although the brake levers on the 'I of M's' are 50% longer than the 'Peat's' - they are only half the thickness which makes them very susceptable to getting bent.
- The lever on the 'I of M' was fitted up side down and because it was held in place by a rivet I had to drill it out - drill and tap the mounting - and fit an authentic looking M2 X 0.4 square head brass bolt - just like the ones that come fitted as standard on the 'Peats'. Now that I'd inverted the brake lever, the attachment bracket for the brake locking pin chain was upsidedown and had to be repositioned.
- The body furniture on the 'Peats' is painted authentic matt black - on the 'I of M's' it's just bare shiny plastic.
- Small details that are separate mouldings on the 'Peat's' are just painted on by hand with a brush on the 'I of M's' - the brackets that join the buffer beam's to the longitudinals - the wrought iron bands on the ends of the buffer beams. (the Peat's dont have these bands, but on the L & B bogie brake van that has similar beams, these bands are separate mouldings.) - and the inboard static part of the side board hinges.
As I said - disappointing ....