Is it time for a console?

PS3 is rather cheap now, but if you wait a little, it may be even cheaper. PS4 has a decent library, but this is the year when games that should actually make people to switch are released. (Then again, last year was supposedly that year as well…)

I say go for it. Buy while games you want still have a chance to be found in local stores and PSN still does sales on games for it.

Do not get a 360. It had some interesting exclusives of its own, but system issues were more common and unless it is different in other countries, digital sales weren't that common. You also need to pay to play online, while the PS3 doesn't stick it behind a paywall.

Rocksmith will lag also on the PS3, the "ideal" way is to plug the console or PC to your TV and disable filters and/or enable game mode, connect the audio to EXTERNAL SPEAKERS (or audio system) using the line out or headphones jack on the PC or composite RCA cables con the console. Also configure the lag on the game to match your TV.

I play Rocksmith 1 and 2014 on my laptop connected to my TV and I can play it fine. I also own a PS3, is a very nice console with huge library of games that now can be bought for cheap. I now play primarily on my laptop (was a huge console gamer) but with Steam on Big Picture mode using my DualShock3 controller with the laptop connected to the TV. Still I think that there are some awesome exclusives you should play on PS3: inFamous, Uncharted 2 and 3, The Last of Us, God of War Trilogy, the full MGS saga (as you mentioned).

It also works great as media center, you can stream content from your PC (thoug I believe there's some limit in the number of songs it can read), it plays blurays, has youtube and netflix apps, and can play content from USB drives.

do a lot of reasearch before deciding

Nope, pc master race

it's a tough one. personally I'd be tempted to pick up a PS3 as there are a few games not on PC that I'm interested in, it can also double as a blu-ray player and the prices will probably continue to drop as PS4 becomes more popular (I do think they jumped the gun on launching the next gen consoles without having a more noticeable performance improvement and software library ready though) but on my current finances I can't justify it yet
but if you can afford it and would get some good use out of it then go for it. as much as I prefer PC over a console, I can't deny that the consoles do have a few perks