We've had the Talis bags for our Specialized Vados for ~18 months. Very nice bags with a top handle, shoulder strap, and rain cover. Our flashing tail lights clip directly onto a loop on the bag. There are a couple of mesh pockets on the inside that work great for ID, etc. The Racktime rack on the Vados is the narrow version but the rack adapter on the Talis adjusts without tools for either width. Snaps in and out of the rack easily. Seems very securely attached, even with extra water bottles, snacks, tools, etc.
The Talis does not come with a lock to secure it to the rack, but these can be purchased separately. I recommend the locks so you can leave the bag on the rack for a short time without worrying about it. We keep the locks in one of the mesh pockets in the bag.
We bought our bags from a Euro-based online bike shop, bikeinn I believe (a part of tradeinn BTW). They offer free shipping for purchases over $106 with no US sales tax. Easy to spend that kind of money with some of the prices they offer!