Let's start with the biggest questions first:
As of right now...

Is the game functional?
Yes. It's been on a very slow, but fairly upward trend in terms of functionality. The servers work, and the bugs have been and continued to be ironed out as things move along.

Is the game worth the price?
For base game, yeah. The price tag is pretty good, and the 2 free heists so far sweeten the deal even more, but the most recent single heist DLC is vastly overpriced, and I wouldn't recommend getting it unless you've already got the season pass, or it's on sale.
The season pass currently is only available for holders of the Gold or Silver edition, and they've not made good on their promise to allow players to purchase it post-launch. So I'm gonna give even further warning to either only buy base game for now, or just wait for a sale.
(Sale, preferably.)

Is the game fun?
Absolutely. They have done a good job mechanically with the gunplay, cooperation, the stealth overhaul, quite a lot under the hood honestly. All-in-all, I'd say it's a good objective based horde shooter where it stands.

How about the XP system?
It's... still not that great. They've improved it a bit, but it's still far from satisfying to level up the guns and yourself. It all becomes a mind numbing grind, if you're aiming for some very specific, level locked something-or-other.

Is the customization any good?
The fact that some masks can't be customized at all is a huge bummer, but ultimately not the biggest deal in the world (at least to me, personally). The gun customization is different to Payday 2's, but also has it's own bit of flair to it with weapon charms and stickers to go with the customizable paint jobs. And those that fancied the tailor packs of Payday 2 will like the return of clothing and glove choices as well, although costing C-Stacks, which brings me to...

C-Stacks? What's the deal with those?
Payday 2 had a problem with money; It was too easy to have more than you'll ever need. So in come C-Stacks. They're a different form of currency, that're bought with your earned money, and used to buy "higher tier" things. Cosmetics, paints, stickers, gloves, clothes, masks, weapon presets. And for some reason, specific weapon parts, which do offer weapon stat changes.

Well, what about the music? No more Simon, right?
Yes, Simon is gone. But Gustavo has been doing a pretty solid job of picking up where Simon has left off. He had some experience, doing the last several Payday 2 tracks, and has managed to create some pretty good stuff in what we've seen so far in Payday 3.

Alright, alright, so then would you say the game is at least worth getting?
If you have friends playing it: 100% yes.
It's probably some of the most fun I've had recently co-opping with friends.
If you're looking for a solo purchase... I'd say wait. While you CAN play it solo, I'd say the fun is far better with friends currently.

Let's start with the biggest questions first: As of right now... Is the game functional? Yes. It's been on a very slow, but fairly upward trend in terms of functionality. The servers work, and the bugs have been and continued to be ironed out as things move along. Is the game worth the price? For base game, yeah. The price tag is pretty good, and the 2 free heists so far sweeten the deal even more, but the most recent single heist DLC is vastly overpriced, and I wouldn't recommend getting it unless you've already got the season pass, or it's on sale. The season pass currently is only available for holders of the Gold or Silver edition, and they've not made good on their promise to allow players to purchase it post-launch. So I'm gonna give even further warning to either only buy base game for now, or just wait for a sale. (Sale, preferably.) Is the game fun? Absolutely. They have done a good job mechanically with the gunplay, cooperation, the stealth overhaul, quite a lot under the hood honestly. All-in-all, I'd say it's a good objective based horde shooter where it stands. How about the XP system? It's... still not that great. They've improved it a bit, but it's still far from satisfying to level up the guns and yourself. It all becomes a mind numbing grind, if you're aiming for some very specific, level locked something-or-other. Is the customization any good? The fact that some masks can't be customized at all is a huge bummer, but ultimately not the biggest deal in the world (at least to me, personally). The gun customization is different to Payday 2's, but also has it's own bit of flair to it with weapon charms and stickers to go with the customizable paint jobs. And those that fancied the tailor packs of Payday 2 will like the return of clothing and glove choices as well, although costing C-Stacks, which brings me to... C-Stacks? What's the deal with those? Payday 2 had a problem with money; It was too easy to have more than you'll ever need. So in come C-Stacks. They're a different form of currency, that're bought with your earned money, and used to buy "higher tier" things. Cosmetics, paints, stickers, gloves, clothes, masks, weapon presets. And for some reason, specific weapon parts, which do offer weapon stat changes. Well, what about the music? No more Simon, right? Yes, Simon is gone. But Gustavo has been doing a pretty solid job of picking up where Simon has left off. He had some experience, doing the last several Payday 2 tracks, and has managed to create some pretty good stuff in what we've seen so far in Payday 3. Alright, alright, so then would you say the game is at least worth getting? If you have friends playing it: 100% yes. It's probably some of the most fun I've had recently co-opping with friends. If you're looking for a solo purchase... I'd say wait. While you CAN play it solo, I'd say the fun is far better with friends currently.