I have the KK R&R Fluid Trainer. I've had it for about 4 years (IIRC) and have been totally happy with it. Fluid resistance is very smooth and it is relatively quiet. To me the lateral motion that it allows is a big plus. Has a more realistic road feel especially when sprinting out of the saddle.
The negatives are that it is not a smart trainer so if you plan on getting on Zwift it will limit your ability to access all the features since the resistance will not be controlled by the program. It also has a large footprint to allow for the rocking motion. Aside from that it recommend it without hesitation. I must say though if I was in the market to purchase a trainer now I would most likely be looking at a smart trainer.