Agree with you 100%
I know to many the 5" screen is small. But when you have been reading ebooks for 7 years on Pocket PC's, Palms and iPhones..... the screen seems huge. The slow response does take a bit of getting used to, but you will find it becomes a rhythm of it's own.
Be careful of the Amazon DRM. While many of their books are easy to liberate, the "topaz" scheme is still not cracked. I had a few Kindle for PC books before I got my reader, and about half of them I was able to liberate, but the other half was a no go. Kobo is an excellent book store as well.
Calibre, as you know is an excellent tool.