They are great. Probably best on market IMO. I trust my life to them.
Small needs and possibly bugging out? Travel Berkey (small, stacks into itself) and the White filters are tougher for travel. I think the Black filters are a LITTLE better but you're covered either way. The filters are the heart of the system. The Travel is my emergency prep item (with spare sets of filters to last a lifetime -- also a few pounds of Shock on hand). I have their steel spigot and keep the standard plastic they come with as backup because I think it it a physical weakpoint.
Bugging in or daily use? The Berkey Light (plastic) is a good buy I bought for people when they were a little less expensive (price really went up on all over past couple of years) and you can "make" water as fast as you'd like with their current four-filter capable Light (it used to be only two filter capable which I thought was adequate for most uses but you may have high use requirements). And with the LED light they are just pretty -- like a piece of mood-lighting art in the kitchen! Personally, I use a stupid Brita filter for day-to-day drinking water now -- lol -- do NOT rely on Brita's for much of anything when it really counts/water is questionable.
The steel Berkeys are professional, tough, stuff.
Oh, the additional sets of filters, the Fluoride-etc. ones, do not last nearly as many thousands of gallons as the core Black and White ones. I have them too, including backup sets, but don't plan to use them unless there really are the worst of circumstances blowing our way.