Yes.
Quan will harass you from fullscreen in either an armour spell, with a bat that combines with rune/skull/mb rune or F3/MB rune/skull, when he lands that one hit which 90% of the time will come from a 50/50, he can rush you down in these ways:
Warlock: Land a hit and do a meterless 35/40% midscreen or in the corner, you can skimp on about 4% and go into a MB sword to guarantee a 50/50 situation as you're +90. hitconfirm on block into your MB rune and be +15, which leads into another 50/50 or a jump in if you read the backdash. Or even a throw which leaves you back into that neutral state that lets you fish your a super + D4 or check them with your b2 or f2,1,2, which can be hitconfirmed into a full combo. Let's not forget how the MB Low scoop allows him to interrupt strings and counter poke after situations being minus tricks people into pressing buttons, again, landing you a full combo. Once your counter poking starts working, the opponent starts respecting the option and blocks low, which in turn gives you more 50/50's.
Summoner: Win the entire game by either crazy zoning, or win the round off one touch because of the Summoner Vortex. Not only that but he gets the absolute most combo damage in this variation without question, which leads into hard knockdown psuedo unblockable with low bat NJP. Let's not forget Quan's NJP is one of the best in the game, so the wall of defense is only half of what he can do in Summoner. The rest very much IS rushdown.
Sorceror: Do 70% of your health for blocking, there's sweet FA you can do about it. Not much to say there. He can also guarantee an armour spell under himself while you're on the floor, good luck getting out of that in the corner. That's even if he opts to use the armour and doesn't just rune trap you instead.
All 3 variations rush down in their own way. The fact he's minus is sometimes bad, but gives you options depending on the variation you selected. He is one of the more versatile characters in the game when you take all 3 variations into account. Give Quan a wakeup attack combined with all this stuff he can do, good luck!
But let's keep downplaying him because he has no wakeups