Be wary of placing too much similarity of FMS to the actual plane, some do have a real likeness like the e-Flight Mini Funtana and Seb Art Katana (taking into consideration there's always going to be a difference between a SIM and the real thing) but others are terrible as you can alter how they respond and feel so it's down to the creators interpretation.
My everday flyer is an Acromaster which I love and yet the FMS one is horrible to fly, the Extreme Flight Extra on there is very realistic for throttle, ailerons and elevator and yet the rudder may as well not be there as it's totally in-effective and if you try and hover and it's virtually impossible as it falls out to the side, the Zoom it's like someone tied a brick to the nose of a very lightweight foamy as the CoG is way too far forward and it's very nose heavy !!!!
Find the right planes and FMS is fantastic, have learnt and practised all 3D on there before trying it at the field including harriers, rolling harriers, blenders KE spin and hovers etc and is great for learning the sticking and still use it often now especially for learning new things !!!!!!
Just as a general rule the E-flight ones are quiet accurate to the extent I think E-Flight may themselves produce and post them as they consider if soemone goes in and flys a plane that feels nice people are likely to buy it so it's good advertising but if it flys like a pig carrying bricks then it'll put people off.