It's been quite a small bit of time, now, but IIRC I had some direct correspondence with the author/creator of Readable, and he was a quite agreeable chap. I realize this doesn't speak to the technical merits, but the exchange left me feeling more comfortable about using his product. (Leaving aside the role of advertising and the need to support sites, a separate but not insignificant concern.)
Here's the old URL/site, which is also more visible with Javascript disabled.
Glad I made an impression; and thanks for the compliment.
I'm actually about the same in real life, too.
Don't worry: Readable won't ever have advertising -- the most I'm looking for is something like a very small "Sponsored By XXX" banner, at the bottom -- if any cool company will ever be interested that is.
The new site will be redesigned -- and it will be a lot better when JavaScript is turned off. But I really don't recommend you use the old site any more, as that still runs the old version of the application -- which is way worse, in terms of performance.
I hope you're still using Readable, and that it's still helping you read the web more comfortably.
Here's the old URL/site, which is also more visible with Javascript disabled.
http://readable-app.appspot.com/