The 2.5 were great at the time. They were very inefficient (I think they tested out at about 83 db) but also had very deep bass capability. The d-40r doesn’t go as deep, but has plenty of bass. The highs and midrange in the d-40r is quite superior to the 2.5. I have owned both speakers and had them in house at the same time.
I would look for a used pair of d-40r. They provided a significant upgrade to the 2.5.
If you have a small room I would look for the d-30r.