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One thing Persil surely isn't is a bargain brand. Maybe Persil is taking Wisk's shelf space, but it's not replacing Wisk in any other sense.
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Exactly. Indeed, I was irritated by the official Wisk announcement that said basically: we're going bye bye, but you can buy a more expensive detergent instead!!!! A more appropriate suggestion, I'd think, is All (and, in fact, I think they suggested All for people insisting on unscented detergent).
I haven't used Persil, but I assume that it would have better cleaning power than Wisk. That said, it also has a much higher price tag.
I have a nearly empty bottle of Wisk that I got last fall. I was frankly not wild about it. It was a good buy at $3, and did reasonably well with my typical load, which is mostly about freshening. Although much of the freshening it did was actual cleaning, and how much was just the impression of freshness due to the perfume stench is debatable. But I really don't consider Wisk that great. It's was an OK budget buy. But I'm not sure that it really should rank as #2 detergent. Although perhaps the formula CR likes is different. (I got non-HE, and perhaps they tested HE.) I can say that recently I started using All Free Clear Oxi, and I can't say I noticed much of a difference between it and Wisk. Except All Free Clear doesn't have a lingering scent stench, of course.