Dodgealum,
If you hang out at HUG, you should know that there are no speakers that are significantly better than Harbeth :-). Seriously, there are different listener priorities and different product strengths and weaknesses - there isn't anything that will "exceed [Harbeth] by a large margin", especially if you like the Super HL5s. As you know, the Harbeths are very natural with great tonal balance, but they aren't the last word in PRAT, don't have spectacular imaging, and the monitor 30 and 40 speakers use the better Seas tweeter. It's all about priorities and having fun trying new things.