I used Forlife neat (or it's pointless) for 10 years in one Healey 3000, 6 years in another and 4 years in my Interceptor. It's very good - no signs of problems anywhere, ever. Never changed it, just drained to do engine work and put it back in again, as the manufacturer suggests.
Two years ago I switched over to Evans, as it makes superior claims for cooling. I'm not convinced they're well founded, but it too works well neat.
I haven't used standard antifreeze/water mixes in my proper cars for over 15 years, and I'm not about to go back to them. I had to drain the Healey's system a few months before I sold it (fool), and after 10 years the fluid was bright, clean pink, the waterways clean and smooth. The only drawback is the cost.