Speaking of realistic loads, believe the old-school "windtrainer" style still has a lot going for it. I don't ride trainers too often anymore, but prefer the my Blackburn Windtrainer to the newer "Travel Trac" mag-load unit for it's realistic aerodynamic load curve. In addition, the fan and flywheel will never wear out or need calibration. Workload is always repeatable since it's based only on the speed displayed on the bike computer. Also, load capacity is virtually unlimited, since the work goes directly to the air flowing through the fan, not into a small load unit which heats up as the session progresses.
Not sure if any windtrainers are still on the market, but for those who train in a garage or basement and don't need to worry about the noise, IMO they are a great option.