Picked up my 28 f/2.8 IS for 350 during the last holiday season's sales from one of the NYC superstores. It's a nice lens, but not very popular.Wow, you paid a good price for 28mm IS. It is a shame that other countries outside the USA there is no discount on prices of lenses. However, I actually prefer the focal length 24mm APS-C. Actually, I'm very envious of EF-M 22mm F2.
The 24 is more useful than the 28, but the 28 was on sale and the 24 was not. I think the 24 and 28 f/2.8 IS are more suited to FF because there are so many zooms that have IS for APS-C in the range. IS can be useful, but I don't use it much because most of my pics have people in them and I typically need a faster shutter speed anyway.
Agreed, the EF-M 22 f/2 is a gem. The smaller and noisier the sensors, the more "necessary" faster lenses are...