it depends on your needs and room size.

s1000db is good for close range listening and far range music listening.

those with subwoofer (c3x and s530d), need some extra legroom.
medium to big room is recommended for 2.1 speaker setup.
small room tends to echo the bass.
subwoofer one are good for movie with lots of explosion or bass.

if 80% is music listening (s1000db or the latest s2000 pro from Edifier).
if 80% is movie watching (explosion) and gaming (explosions), then c3x or s530d.

If you are used to Edifier Luna Speakers, there is a possibility where you may not like the R2730DB (or any of the Edifier studio monitors lineup such as the R2700, R2730DB or R2800). Reason being, the highs on the studio monitor is significantly much lower and does not feel "forward" enough even after maxing the treble to its max. I discover this after comparing between the S1000DB, S2000DB ad other non-studio Edifier bookshelf speakers. Personally for me, listening to studio doesn't make my ears fatigue compared to non-studio, perhaps I'm so used to studio speakers (using it for approximately 2 years) :-)

The interesting thing I love about Edifier's studio speakers is gives a feeling of a 2.2 speaker (as if dual stereo bass projecting towards me instead of a single strong bass from a subwoofer)

R2000DB bass is super strong and hard, and treble can go very high to satisfy treble-lovers. For me, I'm favor mellow bass and R2000DB plays bass really hard which I feel is not as natural compared to Edifier studio's speaker and 2.1 speaker system. Both speaker R2730DB and R2000DB has Bluetooth and optical, so its good.

Since you have a 2.0 speaker, why not a 2.1 speaker? (something different a bit) The one I would highly recommend would be Edifier latest 2.1 speaker which is Edifier S350DB. I found this speaker on promo on the 11.11 Single event for around RM850 which is a great bargain (MSRP RM1,1K+)

You can audition Edifier speakers in Lowyat IT stores such as Viewnet or Sri Computers as they have demo units there OR visit https://www.facebook.com/StarsPickerAudio (Star Picker Audio Cafe) as they have demo units for Edifier higher end speakers.