nothing like that mate, the 34 is a single choke carb, a reconditioned and rebuilt standard carb would be better than a 34ICH.
the standard carb is a twin choke, where as the weber is not. also you'll lose the auto choke. and if your fitting it to a car with ECC you'll need to replace the inlet manifold with a standard one (guide for this i wrote up in the DIY section)
theres no doubt fitting a 34 makes a good improvement in throttle response but then any new carb would compared to a 16 year old tired standard carb i've had a 34ICH on all my previous micras and yes it was a little better on response but nothing amazing prb a maximum of 3-5hp.
HOWEVER!!! the MPG you can achieve from fitting a 34ICH is massive! i managed 100 miles from 1/4 tank (motorway traveling at 56mph) its was just incredible!