As is the case with all HiFi gear, 3030i are more expensive here in Serbia than in the UK (approx. 345 Pounds at the official importer, while Concept 20s are around 300 GBP).
Hope I'll find some good deal on them soon, so I don't overpay so much.
Didn't hear the Concept 20s, I'll try to audition them as well, but as you said, if they are shy on bass, I would skip them, regardless of the refinement. Judging from the 3020i experience, if 3030i have a similar sound presentation, with the added bass presence, I'm going to be happy with them.
My goal is to clear the subwoofer from the equation - presently I'm using an old Yamaha sub, but I'm not satisfied with the quality of the bass - there is a lot of it, but it's mushy. I will settle for a bit less bass, in order for it to be more tight and precise. And it's less hassle as well.
Don't get me wrong, the Concept 20 is a fabulous speaker, even at £300. They don't have much bass extension though. They go down comfortably to 65Hz in my room when positioned about 20cm from the back wall, but there is nothing below 60Hz. The bass you do get is tight and punchy. Just don't expect to hear those low notes at all. You really need to pair these with a subwoofer for best results, as you would with the 3020i. I don't feel I need a subwoofer for music listening on the 3030i.
As for room issues, this is where the Concept 20 really shines. Those cabinets are so inert they feel almost like they are lined with lead. I am using them on a desktop PC setup, stuck in a corner with very poor acoustics. I tried the 3030i there, and despite being very good for near-field listening, the bass was very, very boomy and the imaging and soundstage no worth even mentioning. The Concepts though...well, there is no boom. I know they are missing nearly 30Hz of bass extension, but even similar sized small bookshelves boomed in this position. The Concepts also image well despite the location, providing a nice soundstage where other speakers struggled. The 3030i needs a little more room away from side-walls and the back-wall, but are still very easy to set up. I found they work better in this regard than other speakers of a similar size and price, such as the Wharfedale 12.2, Dali Oberon 1, Dali Spektor 2, Monitor Bronze 2, 50 and 100. The only speaker that we easier to position was the Polk S15e. But it doesn't have the same bass output as the 3030i. I am using them in a small room (4m x 3m) with bare walls and little furniture, in a sort-of-nearfield setup (speakers 1.5m apart), and they are great. Sure, some room correction would probably improve the sound, but I have great bass, no boominess, a wide detailed soundstage, nice imaging. So, I saved the money and bought more music
As for the difference in sound between the 3020i and 3030i...it is more than just adding more bass. The frequency response has measured as a bit smoother and flatter. The midrange and treble are slightly improved, so I am hopeful that you will be more than satisfied with the upgrade.
Sorry to hear about the high cost though. It's the same in Greece. We are rather spoiled here in the UK. Good luck finding a good bargain