Vacuum filling is great and once you do that a few times you realize it's the only way to go. I personally have the mityvac mv4525 as it is a system pressure tester, t stat temp tester (works so/so), can give clues as to a blown head gasket with a running pressure test (building pressure with no or low heat increase), and also a vacuum filler. Another great thing about a vacuum filler is if doing any work on the car that required coolant parts being replaced then you can draw a vacuum and let it sit and verify it is sealed before dumping coolant and letting is run only to find it leaking and now lost 40.00 on coolant.
Mityvac
I don't remember the price but not bad for multiple all in one tool.