Always great animation. I have been using the Haimer for quite a few years, and seem to go through at least two stylus a year, as they break very easily. I always try to securely hold the Haimer, but can be a problem if you need two hands to say loosen and ER nut. I also try to avoid using the power feeds, if you overshoot the stylus will disintegrate. One issue with the Haimer's in the US, is that if damaged, it needs to be sent back to Germany for repairs and often will cost as much as a new one. I have a back up Tschorn, which has repair centers in many countries, they will send a factory repaired exchange unit for about half the cost of the Haimer. Stylus cost has also gone up, I always try to keep 1 or 2 as a backup.
Accuracy wise both the Haimer and Tschorn should get you into the 0.0004" range if setup correctly, Haimer has been a bit more finicky then the Tschorn. As you mentioned, they work great for finding centers on round stock and holes. I also have a touch probe for my DRO, but do not find it to be as accurate.