My view is though that it will potentially disadvantage you in the end (although you'd never be able to prove it because they all make all the right noises). You will not be given 25% extra time to complete tasks in real life. You just can't be. It's not the reality of the job. As such, I think whilst HR will make the right noises to avoid claims of discrimination it will ultimately disadvantage you if you require extra time to do things that others do more quickly.I have personally always asked for 25% additional time for written exercise ( for adhd and another condition) but never disclosed the reasons unless asked which has never happened so far. While I don't have a TC yet I did get VS/ACs for DTC without this being an issue.
I have made an application for a particular firm two years in a row. Practically the same application. First time I didn't progress very far at all but the second time I didn't disclose my issue or request extra time and I'm now at final interview stage.
I've done far better with the firms where I've not disclosed any issue (even though I clearly would have preferred extra time for certain tasks!) than those where I have.