SPARTAN ImageBrowser is OK, not bad, not great. The worst part is that it can't read .tiff and can't send back a photo to the camera – it WAS (!) possible in OS 9... It's not too slow and stability is great. There are faster tools to sort photos, better tools to archive pics, this one is not the best, it simply works.
But the real gem in that Canon suite is DPP. Its conversions are far superior to Camera RAW / LR / Aperture / C1 / etc. conversions.
Image Browser worth a 3/5 and DPP a 5/5.
(Version 5.8b)