I like them both. They’re somewhat different, even though both are light clicky switches. To really make it a fair comparison, you have to take the SMK (“monterey”) switches out of the terrible cases they mostly come in, and replace the terrible thin ABS keycaps. You want to make sure you get a good condition set of Alps switches, as switches filled with dust/grit get much less pleasant.
Blue Alps feel a bit more refined/classy. SMK clicky switches are a bit more tactile. Alps switches have an earlier actuation/tactile point. Blue Alps in particular are very smooth and feel stable/solid all the way through the stoke. Blue Alps are a bit quieter but I prefer the sound to the SMK sound.