How many P64 users out there use the grinder for both brew and for espresso?

I know that many that are deep into the hobby prefer one grinder for each use. But I also know that some of the higher-end grinders are okay at switching back and forth. How does the P64 handle this? Do you still think it is best to have two grinders or can it do double duty?

I do this daily. I do have the MP v2 burrs on them so I think I get a better v60 grind that I would if I had the HU burrs. it's very easy to dial from espresso to v60 and back without retention so no need to purge.

Nice. The one I just bought used from Prima has stock burrs so I was thinking of acquiring Unimodal burrs.

I'm not sure how the Stock burrs do for coarser brew methods, but they may not be the best for it, judging by the description and generalizing that lower clarity burrs that are more traditional style which work well for medium or darker roasts, but usually have more fines and are not great for coarser brew methods, I'd say it's worth upgrading to any of the SSP options if you want the best quality brews.
The Cast sweet lab style burrs are supposed to be filter oriented but work well for espresso I find, a bit more body and not as much clarity but still pretty good. The Unimodal /multipurpose burrs are best for high clarity on light roasts, and probably best for brew as well.

I mainly do espresso and don't switch between espresso and aeropress often, but recently did a test, and the P64 actually didn't do so well with retention without a bellows or purging any coffee through.
I put in 16g and got out I think 16.8g (so 0.8g of espresso sized coffee came out) which was more than the DF64 was off by after using bellows (0.4g) and my other single dose grinders which were pretty much spot on Monolith Flat and Weber Key.
But I don't think that's usual, and you don't need to purge coffee when changing coffees or grind size or anything.
The Aeropress I made with the extra .8g of retention I thought was a bit more bitter than the other grinders I tested against as a result, as it cooled I think it somehow went away and I also enjoyed it, still turned out pretty good.
Basically if you're switching back and forth like every day, I'd get a little bellows to blow out any extra grounds that may be hiding in the chute or something. Otherwise maybe throw in like 0.5-1g of sacrificial coffee.

have you tried using your palm over the opening and creating a 'hand bellow' to express grounds? I do this, along with RDT, and have essentially no retention

Same as I do. Switch between espresso and filter daily

Nice to get more confirmations of users going back and forth.

Of course, I understand the desire to have multiple grinders ("toys") as I also have that itch. And then we have the conical vs flat differences. And also historically, to get the most out of coffees that have quite different grind sizes. BUT with the advancing tech/design of the grinders themselves and now the push for different burr styles, I was thinking (and hoping) that more and more SD grinders out there are competent to switch hit.

In this hobby it is very tempting to fix "problems" that do not really exist - or at least have very diminishing returns
I have the SSP MP burrs in mine, and I have sometimes thought about getting a complimenting conical for thicker shots and milk drinks, but to be honest I am still more limited by my (growing) experience and knowledge. I have started understanding how certain coffees and brew profiles let me produce very tasty, more traditional types of espresso if I feel like one - although it will never quite match the body of a medium-dark from a Niche.

In other P64 discussions threads ppl say it is easy to go back and forth. I'm in the camp of, if you have a P64 level budget then something like an Ode is relatively cheap as a future add-on and allows you to leave your P64 dialed in to your latest espresso. Plus, you have the option to swap burrs back and forth, like, if your P64 happens to come with unimodals you can transfer those over to the Ode.

I agree completely! Isn't the point of a SD espresso grinder, single dosing espresso? Why would you be constantly trying to adjust back and forth when consistency is the objective?