No there not, Deore is half the price and you can get lighter trigger shifters.
But having not used the x0 then i might not be making a fair comparison, i still find it hard to see how they could be better, i just dont like the motion of the grip shift.
You can pick both up for around the same price if you shop around. The only lighter shifters are either XX, X0 or XTR, all of which are much more expensive.
And X0 shifters are miles different from cheap and nasty catalogue bikes, they’re even miles better than X9. You should really try X0 gripshift before slagging off all gripshift as rubbish, I love mine to bits.