Thinking of upgrading speakers from ProAc 3.8 I have enjoyed in my system for 23 years.

-1 on Sonus Faber, company has the worst customer service imaginable and their distributor here in the US is worse... will never get my $ again. Having said that I'm using Audio Note, AN-e these days. May not be as sexy (subjective) but they are spectacular in my all tube setup. Just my opinion 

I encourage you to listen to as many speakers as you can. Technology in materials, electronics and usage of computer aided design continues to evolve and I think results in excellent speakers at many price ranges.

• If you like your current speaker, find out if you want to stay with ProAc - they make excellent speakers.
• My experience with Sonus faber has been excellent- I haven't spent much time with the Serafino G2 but I find their sound appealing and currently have Olympica Nova Vs which I'm love
• I'd encourage you to hear Devore speakers if you can

Good luck and enjoy your journey!

I have a pair of 3.8’s that I like a lot. 
I have heard the TAD ME1’s several times at

Axpona and have thought they would be a worthy upgrade with a nice sub.

Thanks @fastfreight. I think K8 would be too big for my room. I can't find that listing though.

Thanks all for your replies so far.

I am leaning towards D48R. I will look for an opportunity to listen to SarafinG2.

I am in no hurry, 3.8’s are sounding good today.