No I would not. For T8 the security experience, even for TSA, is fairly crummy, so it's marginally better that TSA PreCheck (perhaps). For LAX and MIA PreCheck is as good or better. I haven't done the ORD Flagship for some reason, so I can't qualify that one but PreCheck in the USA helps one's sanity frankly. The CK guide may help if you aren't familiar with an airport, but otherwise they chat so much that it slows everyone down.

The one thing I should point out is that there is no escaping security. Now PreCheck security is essentially like going back to the mid 1990s, the main nuisance is coping with travellers who can't get their minds around it. Now if there is only one or two people in front of you then it doesn't matter what the label is, PreCheck, Flagship, LHR Fast Track - you're going to be through in a few minutes. And that's all that matters to this traveller - special arches, separate entrances really mean little to me, and Premium Gatwick rather proves that point - it's slower than normal security but people think its exclusive since they can't see how the other 90% live.