Can someone recommend good mechanical keyboards?

There are different mechanical switches like Cherry MX Blue, Red, Brown, etc, etc. Red seems to be the most popular switch because it doesn't take that much force to press the keys. Brown is in the middle and Blue needs a bit more pressure. A lot of this has to do with the size of your hands and fingers. If you have small hands and fingers then MX Blue probably isn't for you.

I used to buy Razer keyboards and I've bought about 4 of them and so far 2 of them have broken. IMO, they are not all that durable. Last year I switched to Corsair and the only problem Ive had so far is one of those Corsair keyboards had the lighting malfunction.

They make downloadable programs for these keyboards but it seems most of these programs are written for RGB keyboards.

I suppose you can try a Razer Blackwidow if you'd like to. Best Buy usually has these and sometimes they're on sale. The Corsair k70 is also good. I've bought a couple Corsair K95 keyboards along with a Corsair k70 and 2 of them are working fine. I'd actually suggest going to an electronics store and trying to see how they feel to you before buying one.

As far as the rest of your build goes, do yourself a HUGE favor and wait for Intel to release their Coffee lake 8th Generation processors before buying anything, unless you plan to buy Skylake-X LGA 2066 parts. Intel is supposed to make an announcement regarding Coffee Lake on August 21st. The Core i7-8700k will have 6 cores and 12 threads and the Core i3 processors like the Core i3-8100 will be quad-cores. This might put a huge hamper on AMD's comeback, well at least for gamers.

Are you talking about the older style of keyboards with the clicky microswitch keys? If so, those things are made to be very durable so you're probably good with any brand you buy. They'll just cost a little bit more than the standard keyboard with the carbon trace button contacts.