An honest opinion about upgrading?

Not familiar with those speaks and amp, but if those speaks are a difficult load as indicated and the amp isn't up to it, that is the place to focus. Look for a high current amp that mostly doubles output into 4 and 2 ohms. Class Ds are a possibility. The better Musical Fidelity amps second hand are a very good value that might fit the bill also.

In the same vein as Shadorne and Mapman my recommendation would be high current electronics.

I had the Rogue 99 magnum pre and a pair of mono block 120 for a few months and while the 99 pre is pretty popular by demand, I found it was not very detail and transparent. Couple of buyers listened to it with my ML SL3 and they came with the same conclusion. If possible, you may get a ARC LS 25/ 26 as loaner and get some SS amp as Bryston 4bsst, you may be in for a surprise. In my set up, the Rogue 99 would not cut it for me, especially at low level listenning.

I own the Rogue 90 and 99 and they drive a pretty tough load, Dynaudio Contour 3.4s. I've tried a few more powerful SS amps (Plinius and Bel Canto), and I've liked none as much as the Rogue. More bass control as expected, but the Rogue stayed.

I also drove Paradigm Studio 100s for a time with the Rogue amp, and I thought it did just fine.

I recently tried a Cary 98L pre-amp and as Andrewdoan indicated, it was much more detailed and had a much more extended top end. Do I prefer it to the Rogue? I dunno, but if detail and transparency are your targets, you might audition pre-amps. By the way, I use Sylvania 6SN7s in the pre-amp.

If you are not running NOS signal tubes, you should give then a try. They really improve both the pre- and the amp. Better power tubes help too. And those are all cheap relative to a new piece of hardware...

Please do not get me wrong, Rogue makes some very good products for the money, it's a matter of personal preference here. It is subjective and bias when come to 2 channel audio. John Crossett recommended the Bryston 4 Bsst and the Audio Reseach SP16 while I believe the SP16 is dark and bloating in the bass department. As Bobmclean feels his sytem lacking the details and transparency, I would recommend to swap the pre to the Ls25/Ls26 and then amp to the Bryston SS amp. The Cary 98L pre is one of the clean pre-amp where you do not have to crank up the volume for optimum sound quality as with the Rogue 99.His Paradigm S8 ( do not know the version) is a very nice speaker. Good luck and happy listenning.