Again, my reasons for really liking this project isn't because it's going to be the very best summer skiing in the world. I like it because it appears to offer pretty decent skiing, in about 2.5 hours from what I consider the greatest place on Earth- Banff National Park. For me though, Banff is better in the summer than the winter, and given my limited vacation time and budget, thats when I plan to take my family there. Most people would agree, as the tourism numbers show. Now that there appears to be pretty good skiing a short distance by, I'll definitely have to do that... and I suspect there will be many others.
Comparing the choice of going to South America vs Banff/Jumbo it boils down to: "A week of winter skiing at an isolated Andes resort" or a "summer vacation in arguably the prettiest place on Earth, with a side of decent skiing". I'll say it again, that I wouldn't discount there'd be a lot of people like me who'd get pretty excited about option 2.
As well, at 51deg latitude and 10000ft, you've got a shot at fresh snow year round, with a reasonable expectation of powder for 8-9 months a year. Perhaps a Banff local could chime in on that.
Finally, I found this on the BC government flickr site. It doesn't show all the roads, but it appears Jumbo is VERY close to Panorama.
Mount fidelity which is nearby averages 17 inches of fresh in may and 51 inches of fresh in October. Not bad.