I can more easily compare The Mules to the 57 Classics that were in the 335 - I think it'll help, though.
I liked the 57s but they were slightly lacking in something. A little bit of clarity maybe, but something else. I've since read someone else say that the 57's top end is a bit "brutal" as in "unrefined". What they meant was that when you push the amp, it's not entirely as pleasant as it could have been - I seem to recall "bright and mushy" was the description. And they talked about this extra "rasp" they could hear that they didn't like.
I didn't think my 335 was doing anything particularly bad - it just wasn't as wonderful as I imagined it could be. Some days it wasn't terribly inspiring to play.
Now, when I switched, I already knew how the Mules worked in my Tokai Love Rock. I just had this feeling that what the 335 wanted was that vibe (I also considered Riff Raffs for "more rock and roll", and Stormies too - but I didn't know Stormies then, I imagined they would be TOO vintage for me, mellow jazz vintage... I was so wrong!). Eventually I decided to bite the bullet and not buy new pups but spend a Saturday swapping the pickups over to see what happened. The 335 "came alive". It was the same guitar, even the same tone, but just "more". Obviously there was the "new strings and set-up, perhaps that's all you're hearing" doubts, but it's a couple of years since the swap, and everytime I pick the guitar up I love it - new strings, old strings, whatever.
The 57s worked OK in the Tokai - but the slight "blanket over the speaker" moved from the 335 to the Tokai. I've since moved that set into my Explorer, and of the pickups I've tried in there (including Riff Raffs and MQs), the 57s are the most succesfull. But it still has a slight "uninspiring" vibe when compared to the 335 (Mule), my LP Trad (SM), my 61 SG (SM), and my Faded SG (RR). (The Tokai has MQs, by the way - I've yet to really find the guitar that wants them, it's close, but not quite)
Next time I restring the Explorer, I intend to put the 57/57+ set (from my Trad LP) in. I suspect that the slightly hotter bridge pickup might make a fair bit of a difference.
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Now, back to the pots and this guy's "57s have brutal top-end". When I first heard that, I didn't realise that most of my 57 equipped Gibsons had 300K pots. In fact, I don't think I've played 57s with 500K. But I have played Mules and Riff Raffs (and MQs) with 500 - they are fine with the extra clarity, but I can imagine now how the 57 might seem slightly less pleasant (unless that's the tone what you want! I must admit I've seen plenty of guys on Gibson forums etc say, "replace the pots and you'll be good with the 57s, don't waste your money on new pickups").
My gut feeling is that, regardless of the pots that are in there, you're going to find what I found when I swapped the 57s for Mules in my 335 - the stuff you like about the 57s will still be there but improved. The stuff you don't like, the doubts over "is this the best it could be" will be gone immediately, and (if they're the right choice for you for that guitar) won't ever come back.
I know they're different magnets, etc, etc... but, in my experience, Mules (more than Stormies) seem to be what 57s would like to be when they grow up!
In fact, yes -
1) In the 335, I wanted the same vibe as the 57s, but better - Mules did what I wanted.
2) I wanted a slightly different vibe than the 57s in my LP and 61 SG, Stormies did what I wanted.
In all cases, I kinda lucked into it
but I have realised, while typing this reply:
3) It's Mules I want in my Explorer, isn't it?
ALSO!! WOWW! I suddenly have answers for the Tokai and the Faded SG.
1) Tokai gets the Riff Raffs - it can cope with RRs easily
2) The Faded SG gets 300K pots back AND it gets the MQs back (it had them before, after the pot changes, but it was too bright and not humbuckery enough for me at the time)
OK, now I'd better do some work
(mebbe order some pots first
)
