It never occurred to me to detach the pigtail and let the boom fall into the cockpit before raising the main...that seems not quite right, what of the crew in the cockpit? - dealing with a flogging main and boom as it is being raised? Topping lift or attached pigtail seems the only reasonable choice and the pigtail has a definite disadvantage. As far as raising the boom out of the way, I can do that with the topping lift as well. No, I don't miss the pigtail at all.Just don't keep it attached when you raise the mainsail. Without a topping lift the boom will fall into the cockpit when you drop the main. No reason you can't use both to your advantage.
Actually there was another reason I added the topping lift and it was already mentioned - reefing. Attaching the pigtail in need-to-reef conditions is a very bad idea, releasing the halyard drops the boom until which time you can haul in the reefing lines - I tried it once and decided I did not want to do it again.