For what it's worth (not a lot), I would change the oil and filter, add the HPL ECx0 (based off your need) and run the regular OCI. Then, maybe run the EC again with the next oil change. Then take a look to see how you are doing. If all looks well, then run the HPL oil for an interval and if you feel it meets your needs continue. If it doesn't, go back to M1 or whatever brand you fancy. I personally would use something reputable which meets the specs that your car requires whether it be Amsoil, HPL, M1, Pennzoil, Castrol, Valvoline, ST, Kirkland and on and on and on, etc...
I have run engine flushes before. Not sure they did any good or bad. I went a little overkill with mine that maybe others have done. Drained the oil, put new oil in (I think M1), changed filter, did the idle thing then drained and filled with new stuff again and new filter. I know some people will just put the flush in with the oil that is currently in the car. Again, not sure it made a difference. I just did it because I didn't know the oil change history of the vehicles I was using it in or I wasn't a fan of the interval that was used.
I am using HPL Premium in 2 of my cars now. I don't know if there is any sludge or varnish BUT one of those vehicles is under warranty and I do my own changes. IF I have an issue, I don't want them to come back and tell me the engine is sludged up (even though I change every 6m/6k miles). Once I hit that mark, I'll be going back to M1 EP since I have 5 - 6 5qt jugs. The other car had mostly 5k oil changes done at the dealer with what they said ws M1. After 99kish miles I switched to Amsoil SS for some extended oil changes (extended as in more than th 5k I was running but probably less than 10k), then I used Kirkland once and I think the MM was down to maybe 5-10%; I can't remember. Now, the HPL is in there. Once the MM hits 0, I'll go back to Kirkland since I have 9 5qt jugs of it for that car. That car has 138k on it and if it lasts a few more years, I'll be happy. Wanna go a few years without a car payment. I got 6 months left on one of my cars and then I'm done.
So, again that is what I would do. Take it or leave it. Good luck with whatever you end up doing in the future.