I was in a similar situation to you ask yourself do you really need coilovers, if you want to slam the hell out of it or like the idea of being able to raise/lower it or going to be doing lots of track driving then yeah you probs will but if you dont you could always go with a good set of new springs and shocks which is what i ended up doing and itl work out cheaper than ap coilovers not the stance+ tho without compromising to much on quality. I got a set of ap shocks from damien at dpm for a good price then combined that with some apex 35-40mm springs which i got on ebay and have been very happy with the results, the cars still practical, stance looks good, ride quality is pretty much same as standard (always found the fr
ibiza quite hard naturally) not crashy/bouncy at all and good improvement on handling. Remember when changing the suspension its advised to change top mounts and bearings and to replace the nuts/bolts associated with the suspension although i do no people dont do this but it is advised, especially if its few years old these extra bits soon add up on top of the cost of the new suspension so £500 can soon become £600 etc and thats before you have it fitted unless you have the time/know
how to do it yourself.