Should I trade up from a Kavent/Shengya/Vincent mono block ??

Don't buy Ps Audio stellar 
It had no soul in the sound and there is no authority in the sub bass at all 
I owned Ps Audio s300.

Re. Ps Audio Stellar... Respectfully totally disagree... Got one to hold me over until my tube amp got fixed... and was shocked at how good it it sounds.  I was especially surprised being that it was a class d amp... I'd been disappointed by them in the past. 

May be due to to synergy in my system... But one of the best amps I have ever owned. 

As a bonus PS Audio is a great and supportive company. 

So I did the deal with HiFi Heaven and got the M700 Stellar MonoBlocks..
They are fantastic and the best I've ever owned.. A rating in Stereophile ..
A good cheap deal for sure..
I'm running Focal Speakers..

for me...it would be a mistake.  Never liked PS Audio

See I was right ;) ... Sorry was prompted by the original.. Belated reply. 

I’ve got the 300 and love it...

Happy Listening Pauly!