I own original RMas now, soon to be upgraded. I had Tempestas previously. I have found 23" to 28" behind both speakers to be good. I used 7' between the Tempestas, about 8' with the RMa. Sitting 8' from either speaker is good.
I have around 5' to the sides, which I find to be helpful. I don't know how 2 feet would work, as I believe early sidewall reflections are a bad thing for most speakers.
Both models are excellent. My room eats bass; the 7" woofer in the Tempesta didn't fill out the midbass to the degree I prefer; the 8" RMA woofer in a 2x size cabinet perfectly loads the midbass in my room.
Other comparisons- the Tempesta has superior extension and air, and a wider sweet spot. The overall level of detail is very similar, but the balance is a bit different- the RMA is a bit warmer, more "analog", while the Tempesta is more "monitor" like.
The RMa has a larger, more open soundstage; very dramatic. Everyone who has heard them comments on that immediately. The Tempesta is quite good in that regard, but to me the soundstage, midbass energy and handmade solid wood cabinets gives the nod to the RMa. Of course the price is much higher; with upgrades the Daedalus Athenas (or the original price of RMa plus upgrades) are well over $10k; the Tempesta is less than half, or a third in base cabinets. Rick can also build larger versions, with multiple woofers if desired.
I really wanted to keep both, but it seemed silly to use the Tempestas in my bedroom, where I rarely listen. If they fit in my office I would have kept them there for sure.
I love both. Taste, room, equipment matchups and budget are factors.
For me, even at twice the Tempesta's price, given my priorities, system, and budget, I'm satisfied with the choice of upgraded RMas. YMMV!