The Fortius limitations

Yes, although the possibilities offered by the Fotius are numerous... it's got some limitations...

First, if you live in the USA, you can't go faster than 26mph (42kmh), the motorbrake is limited because of the limitations linked to the 110v supply.
If you want to go faster, you must equip a room in your home with a 220v supply, and buy an european version of the TACX (with a 220v power supply).
With my Fortius, in Europe, pedaling on a 53X12 at 104 rpm, I've been able to go over 58kmh downhill, which is about all the speed I could have reached in real life.

If you try to climb a slope over 15%, the tire gets slippery (although I'm using the Tacx "trainer's special" tyre) and it becomes quickly very unpleasant to pedal with a choppy motion. For the moment, I think this is a probleme linked to the RLV, I've tried steeper slopes on VR, and it didn't feel slippery till 20%. More on this later...
At least, when you go on the Computrainer website, they warn people that their device is limited to 15% slopes... I think this is a limit that will never be overcome, as it is linked to the conception of those trainers : a 20mm tire, past a certain applied power , will never have a grip sufficient enough to sustain that same power. I'll try a larger tire...and will tell you about it later...

You can't repeat a short ride right away.
Let's say you've done a 250m sprint on the Velodrome course, and you want to do it right away after a 30" rest, you must record the sprint you've juste done, then go back to the starting panel, then choose that run again, then wait for the PC to load it, then start again... it took around 2 min...
So, if you wan't to do intervals with Fortius, you'd better plan them before...

You can't record the video of your run, this is a thing you can do with some online car racing video games, you can't do that and watch your races with friends.

You can't use the terrains made for the Imagic (Capricorn and Sipscape)... although you can use the terrain made for the Fortius with the Imagic... It's a bit like buying the latest japanese car, and having less options in it than in your 5 years old Chevy.