SecuROM concerns are basically idiotic, and exaggerated to an amazing degree.
SecuROM is copy protection and the implementation can be done in multiple ways - a choice left for the game publisher. The most basic method is CD/DVD based copy protection. The other often used method is based on online activation. During the installation of these games, the installer contacts securom server with the serial key you type in from the box. The key is hashed with some of the hardware IDs, to make it unique for your PC. The game is activated and a file is written to your local hard-disk, so when the next time, game is launched, the local file is referenced.
It's like installing a game with permanent offline mode.
There's no driver level (ring 0) stuff going on in the background. There's nothing that runs in the background, whether the game is running or not. It's a simple check on running the executable. Subsequent re-installs will not cause more activations, because of the local files stored from the first activation.
When a tool says "wiping out traces of SecuROM", all it's doing is deleting these saved activation files. These are not executable, dlls or any other driver file. Some just get spooked because the file names are very long (and contain non-standard characters) to keep the file management somewhat of a hassle.
How the activation limits are managed is also up to the publisher. They even allow simultaneous activations, where you can install the same on two different PCs, and then play at the same time. It's going against the EULA (for one license use), but it's a customer friendly feature even when not misused. You can lend the games to others, have them installed on multiple PCs without worrying about online or offline modes, and patch them independently. Publishers could set the activation limits to some number or even make more licenses available every few weeks.
Between HumbleBundle (the non-DRM sales, not the Steam keys) and GoG, I pretty much only buy DRM-free titles these days. But if I had to use DRM, to this day I think the least bothersome method was what EA had with their use of SecuROM in Crysis, Burnout Paradise or Mirror's Edge. The games allowed multiple simultaneous installs, and only one install time activation. The 'revoke license' option was right there in Windows start-up menu for the game. And EA had also released external tools that you could run to revoke licenses for games (essentially looking at those locally stored files and revoking these) It was much much more flexible than DRM methods used in Steam, or Battlenet for instance.