I will reply to my self
I was not lazy and used search option on site so i found loads of comments..
My conclusion is that J Costa is little faster but pellets wear every 5-6000 km while Malossi have little less power than J Costa but also is less maintenance free.
Malossi in maintenance consideration is almost same as original(pellets last 15.000+-km).
Probably i will go for Malossi but not sure 100% because i found J Costa on discount for same price as Malossi.
I want to change exhaust also mostly for louder(not loud loud) so other drivers can hear-notice me..Here in my country driving culture is on very very low level and noone take bicycle or motorcycle drivers into concideration.
I have Arrow Reflex, Leo Vince GT and 4Road and Akrapovic Slip on, all used but in excellent condition, price is same for all.
Just need to find out what will suit best for Xciting 250 without need for re-jeting carburation.
Any suggestion for exhaust is also welcomed.
Btw on xjr i have custom made twin Race exhaust(most mechanics who saw and hear Race exhaust said that sound and quality is on top of Acrap, LeoV and others) but unfortunately workshop is closed due to illness of owner.
Check on YouTube how they sounded (search Race Ada exhaust not Dragon Ada) because there is 2 manufacturers in same town, but Race was making better quality, which mean Dragon is not bad either.
https://www.youtube.com/watch?v=mqOCXj5o4xc
Beautiful sound on TDB