Valve seal replacement
Overhead valve spring compressor is the biggest pain in the *** of the job, especially by the blower motor.
with compressed air you will hear blow by, possibly air through the carb or exhaust if the valves dont seal 100%. Once the spring is compressed I tap the retainer with a hammer to losen, before I remove the keepers I tap the top of the valve to make sure its seated. I’ve smacked the valve pretty hard to see if will jar loose, never had one fall. The sound it makes with 100+ psi is actually reassuring.
the pressure is on once the keepers are removed. I add grease to the keepers to keep them on the valve.
Rope method seems less stressful.
bottom line, it’s up to you, me compressed air seems easier/faster.