Some of the pros:
Fully crowdfunded, it's not beholden to large publishers who push things out before they're ready.
The graphics (I won't lie, im a sucker for pretty games and it looks amazing)
Open game development. Every week they release multiple videos on the development of the game and frequently answer backer questions.
Multi-crew gameplay. You can play together with friends on large, even massive ships.
Seamless transition from space to planetside. If you'll allow a slight jab at Elite: Dangerous, you don't need to pay extra to be able to land on planets...
FPS gameplay. You can leave your spaceship and/or pilot's seat and walk around, grab a gun and shoot some poor sob in the face. Good times.
A multitude of (eventual) gameplay options like: cargo hauling, mining, salvage, repair, refuel, exploration, research, piracy, bountyhunting, data collection, FPS combat specialist, medical specialist, search and rescue.. even farming.
A starting package is only $54,40 USD. The pledge store can be misleading, and the many game packages/ships can seem very daunting and perhaps overpriced, but you do not need to get any more then a starter package. Also it's a one-time purchase, it doesn't require a subscription.
Long development time
The project has gotten it's share of critisism for it's long development time and concept ship sales.
I feel the most important thing for new backers to understand is that the game is currently in a alpha state and as such is buggy at times, and many of the gameplay mechanics I previously mentioned aren't implemented yet... which can make the current game rather boring. Backing now means you're investing money into a game that still has years of development time ahead of it.
Currently unknown release date
It has been in development for about 7 years now, and a exact release date for the Persistent Universe isn't know yet.
Squadron 42, the stand-alone solo campaign, is currently set to go into beta in 2020. As both games share many mechanics and assets, development on one affects the other. I reckon we'll see more progress in the Persistent Universe as Squadron 42 gets closer to release.
Something that new potential backers should understand is this:
Because this game is crowd funded and Cloud Imperium gets most of it's funding from ship/concept sales, it has received a lot of criticism on being a "Pay to Win" game at best or a "scam" at worst.
To clear things up, it's not a scam. There is a game. You can play it, even if it's alpha. It is being worked on and constantly updated. Every yearly quarter they release another patch. You can find their roadmap on the website.
The Pay To Win model can be argued, I guess, though just having a large ship doesn't mean you win the game. You will need to put time and effort into playing the game to earn enough credits to keep flying, repair and rearm the ships.
As for VR, right now there is no native VR support. Some people managed to get it working in older builds, I don't know if this is still possible. Cloud Imperium has said they'd like to support VR in some way, but right now it is not a priority.
This is just some of the information I feel you need to know before backing. If you have any other questions, feel free to post them here on the forum or on RobertsSpaceIndustries.com/Spectrum.
Again, welcome and hopefully see you in the 'verse.