I've had both the Exotac Polystriker XL and Exotac NanoSTRIKER XL since March and really like them both.
To be honest the Polystriker XL is amazing. Before this is would alway use the LMF 2.0 army.
I would say that it's the striker part that makes the difference here.
I have an old cheap £3 fire steel which never really did much even with the back of a knife but used with this new design of striker almost set the house on fire!