@donquichotte
i have not heard the sp2/3 r2, but historically, the sp2 line was a true two way (with a single tweeter) and counterintuitively, this model was known to have most midrange and midbass warmth of all the 3 founding models (s100 the big brother, sp1 the middle brother, and sp2 the little brother), despite the bass extension to the lowest octave was most limited (almost non existent) - the cost of this warmth was a loss of transparency and tactility through the treble and mids, although the midrange still sounds quite ’beautiful’
the bc1/sp1 was the founding model, with the best midrange magic, very good treble, and decent/passable bass, tremendous overall transparency
the s100 gave you almost as good midrange magic, terrific transparency and coherence, but even more extended highs and significantly deeper weightier fuller bass -- and, very importantly, the biggest soundstage
over time i am sure the revisions to the sp2 series, leading to the r2 designation, gave it (and all their revised speakers) more treble energy and touch more bass speed, but overall, these speakers still all have a more ’rolling’ or ’enveloping’ nature of bass energy, rather than ’pounding/slammy’ bass... this applies to the big bro s100 as well, although once again, each revision improves the slam marginally
(side note - this is why spendor launched the a and d series of floor standing ’modern sound’ speakers... with greater overt transparency, speed and slam - the two lines are as differentiated in style of sound as they are in their appearance)
all this is all a long way of saying, i think the sp2 series is most compromised in terms of the legendary spendor magic top to bottom transparency and coherence, and has the smallest soundstage, so my suggestion to you would be to get a sp1/2 series speaker and couple THAT with good subs for the best sound with the more slammy bass you seek -- or -- just go for d7 or d9’s if you don’t losing a little midrange magic and timbral accuracy for modern hifi traits in the highs and lows
sorry for the meander... hope this helps nonetheless