Well, IMHO, the people of Tatarstan have a much better claim on the Volga Bulgar heritage than the Chuvashes – they were both part of Volga Bulgaria and share its legacy, but the Chuvashes are descendants of the Suvars (possibly related to the Sabirs, a Hunnic tribe which was even part of Kubrat’s Old Great Bulgaria), while the so-called Tatars are descendants in a greater part of the Volga Bulgars proper. Anyway, just like us Danubian Bulgarians, they’ve also changed a lot through the ages, so the question “Who’s the bigger Bulgar” seems rather irrelevant.