I think it depends on your expectations and the tone you are going for. I play in a modern country band, a classic rock band and I jam with a bunch of guys that goes from Eagles, to Metallica to Wild Cherry. I am getting absolutely fantastic tones. It is "modeling" and for me there may be something that is slightly off and doesn't quite feel exactly like a tube amp with an overdrive pedal in front of it cranked to 8.
But, for me there is such a negligible difference that having so many tones at my toes is worth the very slight difference in feel/sound.
Also keep in mind that once you dial in a good sound you may come back to the the next day and tweak it a bit more. Then the next day you tweak it a bit more. Rinse. Repeat.
I used the POD HD Pro for years and it took me quite a while to dial in stellar tones, but once I got it dialed in with my guitar, my hands, my pick, etc I had tube snobs coming up to me asking what I was using. They thought I was using the POD for effects and I had a tube amp as well. I even had POD users coming up to me wanting me to send them my patches. Mixer settings, SAG levels, BIAS adjustments, etc. It all made a difference.
My point is, going into it knowing that 8 times out of 10 you will find a tone that you really dig, but you may need to spend some times tweaking to get it to sound right. Even if it is moving a tone setting 1% one day, 1% more the next, 1% more the next until you get it where you want it. if you think about it you would do the same thing with a tube amp, every day tweaking a couple knobs here and there until you get it dialed. Its no different with a modeler.