Yes it is pretty close to a real 5150 or a 6505 or 6505+
As always when it comes to this it is a matter of taste i also liked the Vox sim very much
Many here also seems to be after ONE kind of sound i am after MANY kind of sounds not just high gain and as you can BUILD your own amp if you like to do that is really awesome especially now when the sound has improved i guess in 10 year or so no one will use a real tube amp.
Well of course someone will always keep the old stuff and never gonna change just like there is people who still use only analog outboards and tape recorder and even release it only on vinyl

 

Yes i also did it some years ago i even set every knob to 12 o clock and did a matching in volume i also got rid of EVERY effect and tried to compare every s.c amp simulation to a head to head test as in every Marshall JCM 800 against each other every Vox AC30 against each other and so on
I also used the MixIR cab sim with the same cab and turn of the cabs on the amp sim that have that option.
For me Revalver was the best one especially the Marshall sound was good and real (I have noticed that not everyone wants reality)
But many sounded very similar and many also sounded crap especially Voxamp and Guitar Rig and even some Amplitube amps not the Fender ones they are good
Some freeware sounded exactly like those "big ones" but then they had no cab so i guess in the end it is all up to how good you make the cab sim as the amps is very similar.
Also i NEVER heard any that could do that almost break up sound you get from a real tube amp