Really depends on what you want the feel to be? I found boss solos to be disappointing because the tight level math. Saves for example, for a solo boss are gonna be so high you have a 10-20% chance of a spell landing. So, instead of going with really cool spells, you go with cantrips that might have a slightly inconvenient rider to slow the boss down. Maybe take out one of its three actions so it cant clobber your martial characters too badly. Speaking of which, since the crit system is <10>, it means that the boss is gonna hit on attacks, thats not even a question, but what is up for die roll is if its going to be a critical hit or not. Something, again, the PCs have a tiny chance of happening on their behalf.
The people I play PF2 with also have experience with many other game systems, which helps a lot. For example, Fate handles solos pretty similarly -- they are very hard to affect and very hard to defend against without assistance -- you need to build advantages.
For me, this is a good feature. I like cooperative play in D&D, so rather than a system that rewards everyone doing their own thing and ignoring everyone else, I prefer one like this, where players are expected to coöperate with each other. I've played a couple of 1-20 PF campaigns, and whenever you see a solo, you know that you need to work as a team to defeat it. In our games this would be a very normal conversation:
"I can attempt an intimidate if you want to wait for that"
"Hang on, if you go after me I can give it an evil eye and make the intimidate easier with some luck"
"Sounds good -- I'll stand 15' in front of it and ready my shield. that'll use up its actions and with luck I won't take a crit"
Ranged people would be spending actions to hide and get that advantage, and spell-casters would be buffing and making terrain effects rather than the traditional alpha-strike damage dealing attack.
I played an investigator in one of the 1-20 campaigns and that was a GREAT class for handling solos. I'd devise a stratagem, and if that looked capable of hitting the (high) defense of the creature, I'd do it, otherwise help someone else.
The big downside is, of course, that if you have players who don't want to play a team game, you are in trouble. For a campaign, they will quickly work it out, but in a con game or one-shot it can be bad. I'd tend to avoid using solos in one-shots for that reason.