I spend a fair amount of time over on /r/ecr, and the Predator is currently tied with the SMOK Alien for Worst Mod Ever. A number of people have reported the 510 coming out of the mod, fire button randomly NOT firing, and the mod bricking itself after a week's worth of usage.
If Sigelei addressed all of the problems with the 213 and fixed them in the 213 Plus, that might be an alright option. I've not read or heard any issues with the Plus, but I do know that the original Fuchai 213 didn't have reliable Temp Control/(TC), only actually fired to 155 watts as opposed to the stated 213 watts and didn't have upgradeable firmware(Which it was advertised as having)
I'd suggest maybe heading over to youtube and seeing if Daniel or Phil have any reviews on the mods you're looking to purchase. Yes, they have some of the longest review videos out there, but they're also the only ones I know of that actually do a tear-down and look at the guts of the devices. I prefer these types of reviews because I want to know if the product I'm considering has cheap internals or shoddy soldering.