Im not going to play 999

Im going to try to hopefully help here. I played through 999 on the DS and I played VLR on the Vita while my girlfriend is currently playing through VLR on the 3DS. They could make 999 for the Vita and it would work. The only scene that they might have trouble with would be the final sudoku scene, but ultimately the two screens mostly make it easier to explain whats happening, its more symbolic and not absolutely crucial to get the plot point across. It may lose a little flare but again it's not game breaking to not have the two screens.

So you've never played 999 and you don't intend to. Thats fine. It is true you would get a certain higher level of appreciation if you play 999 before playing VLR. It's along the same vein as if you played Chrono Cross for the PS1 if you've never played Chrono Trigger. It's not absolutely necessary to play Chrono Trigger to play Chrono Cross, but you do get a bit more enjoyment (And not to add more games to your backlog, but Chrono Trigger and Chrono Cross, two excellent games that you should play if you haven't). The truth is it's a certain level of fanservice that makes the game more enjoyable.

I would have to say to go ahead and play VLR, its a great game with a terrific story and not having played 999 wont make it any less great. The Gold files and the true ending do spoil a lot of 999. If you happen to decide to play 999 after finishing VLR, you won't get the same level of enjoyment out of it. It would be like reading the book Lightning by Dean Koontz (Great book if you like Time Travel stories), if you already knew what happened at the end. You still get a great story, but all the twists and surprises are less impactful because you know how it turns out. Playing VLR before 999 will make 999 less impactful, but in the end if you do decide to play 999 one day, you will still enjoy it for the wonderful story that it is, full of fun room escape puzzles like those in VLR.

Also, at this point in the games lifecycle, there is no shame in emulating 999. The game is hard to find and even if you do buy it online, its not like the money for it is going to the creators or publishers, you're getting it second hand from someone who apparently didn't cherish it enough to hold on to it and realize it for the shining jewel that it is. There are a lot of games for the DS, but by far 999 is possibly its best, next to Chrono Trigger.

Well, I'm not going to tell you to not emulate the game, but I suppose I should mention though that apparently Aksys games has restocked 999 for the DS on their website for $20. As I do see the game being worth the $20, it is harder to justify the purchase of a DS just for one game. I remember being on their site the other day and it was out of stock. I guess with people finishing VLR, there must be an increase in people wanting to try 999.

In all honesty, if I were in your shoes, having never played 999, but kind of wanting to play it but didn't have a DS, I would emulate, and then perhaps when I had the disposable income to purchase said game and system I would, just so that I could have the physical copy in my collection.