how do you use it to go up walls?

Same as plasma I assume.

never that good though as you end up taking your life in a split second!

In game yes, but a good convention for trickers. Also if mappers design around weapons more oppourtunitys will arise for wall climbing. All Q3 has is the ZTN climb for the RA :(

ive uploaded the movie of doing this now. http://esreality.com/?a=post&id=864097