I first picked up Wargame Accessory bases off ebay several years ago. Last Fall I purchased some more when making an order from Scale Creep for some miniatures.
The 30x40mms I got off ebay were second hand (still in packaging) so while I was surprised to find that about a third of the 4 packs were miscut with one side at 28mm and the other at 30.5mm. The 15s and 20s were OK so I figured the seller might have unloaded some rejects.
However, of the two packs of 30s I got last Fall, in one pack there were 14 with a depth of 31mm and in the other there were 13 with depths of 28.5 and 29mm.
I just opened the 20s and low and behold they all measure 21mm.
I haven't contacted Wargames Accessory yet, but this seems to be a case of fairly poor quality control spanning several years.
At least with the bases that are a bit too deep I can trim them. And I suppose I can glue those that are short to non-ferrous base to allow for use in a magnet based storage container. Having done some metal fabrication this does seem to be something that shouldn't crop up so often.
I went ahead and contacted Wargame Accessories and in combination with an order for some additional bases was sent 4 packs of replacements (I had requested 2, but in lieu of free shipping got 2 additional 'replacements' - Not a bad deal).
So, I still feel the QC could be better (my brother is in manufacturing and wasn't either), but Kevin was good about the replacements.