good to know these infos noxi

. And thats so true...the spies are pretty underpowered, compared to other classes.
Since there is no FF every one(especially the pyros :S) shoots on everything that either comes from the wrong direction or is just a few meters away -.-...
Some disguises aren't even usefull...:
Scout is the most easiest disguise to detect(lack of speed).
Medic disguise is just as usefull as a Scout disguise.(he is holding the s-gun)
Spy disguise is just as a scout and medic disguise.(1.he is not disguised, like all spies are 2.he is holding is cold 3. every one shoots on spies[especially the noobs that don't know that you can see by his cloth-color if it is a foe or a friend...])
Soldier and Heavy work but using one of these 2 disguises means that ur moving speed is lower and you won't be able to catch up with a medic or any other class, that is moving)
Sniper is only usefull if you are on a camping-spot(no one will bother you, normally)
Engis are ok, but if I see a Engi moving around(behind) me and I am atm attacking...I know that it is a spy :S...
Pyros that are behind you or coming from enemy lines with full health are to 90% spies.
Demos work quite good....but hey....thats JUST 1 of 9 classes...c'mon wtf...
Backstabing a scout is almost impossible...
Pyros are moving like maniacs...
good Medics turn around all the time and they are faster then Spies...
Heavies are easy targets, from behind...
An Engi is always aware of spies and will shoot on you if you approach to him :S...if it is an Engi guarding something he will hunt you till he has no ammo x.x
and a lot of other things that make the spy underpowered IMO...