Biggest killer of CV joints is torn boots - Grease gets out dirt gets in.
Split boots should be regarded as a temporary measure to keep you going until you can do the job properly. You need to meticulously clean the joint of all grease and dirt, and then check for damage.
You will probably end up rebuilding the suspension.
New driveshafts are expensive, so look after the ones you have
Your wheel will probably not fall off when the CV Joint gives up.
Simon
