First a caveat - I am not a guitarist and use Music Lab, Orange Tree and Indiginus guitar libraries. I tend to bypass the Kontakt effects and use an VST amp sim.
 
I have both Amplitube 3 and GR 5 and I find myself using Amplitube most of the time. I like the sound and I find it more intuative than Guitar Rig.

Amplitube 3 is my go to. Fender, Orange and Ampeg for bass are all excellent. My second choice is a Scuffham. Lately though, I have also been digging Peavey HD for the Classic 30 amp in particular.

Another vote for Amplatube Fender and Orange. IMO even more important is additional cab emus. Recabinet and Audiffex's multi-cab plug-ins have been my favorites for that.
For some reason they give me better/expected results than cabinet impules.

Chances are you'll buy more than one so buy them when they are on sale. IK have sales twice a day everyday!

Chances are you'll buy more than one so buy them when they are on sale. IK have sales twice a day everyday!

 
Not as good as the sale that is going on right now.  I bought Orange and Fender last summer at $49 each and I have been waiting for Ampeg to come on sale again since then.  This sale has gotten me A3, Ampeg, Hendrix and Slash for $99. 

clintmartin
I prefer Amplitube, but it's just my opinion. As was already stated...if you even think you may want Amplitube, now is the time. For $99 you can get Amplitube 3, Fender, Orange and Ampeg, or which ever three add ons you like.

Amplitube 3 is becoming my favourite amp sim......I've always had POD Farm Platinum and used the Toneport DI box as my audio interface + their direct monitoring. If you're using Win 8, you may find their drivers to be "flaky" (driver dropouts etc...) as I did and had to buy another interface. Because I use a different interface,  I now can't use Direct Monitoring when recording as my DI box can only be used as a dongle, and POD Farm can only be used for its plugins.
 
Fortunately, IK's group buy was too good to pass up (Amplitube3 + Fender + Orange + Ampeg) and we may even get a 4th freebie if there are enough people joining in. There's enough amps/cabs/fx's in this current deal to keep anyone happy for a very long time and is a steal to get all for $99.....the tones are very, very good and accurate.  
 
A big thanks to Clint M. for all the great info on this!! I like your guitar tones/songs and of course, respect your opionion.

Thanks Mesh! I'm glad I could help. I have been very pleased with Amplitube. I have a HD500 and DT50, but I prefer Amplitube. (for live work the HD500/DT50 is awesome) I also have the MixIR from Redwirez, but I prefer the cabs in Amplitube. The only thing I wish they would change is...I would like to have an effects loop, to put the delays in between the preamp and cab. The rack effects are great, but they are after the cab. I'll usually just leave all of that off and use 3rd party reverbs and delays. ValhallaVintageVerb is great, and Valhalla Ubermod is a great delay and chorus.

Valhalla has definitely been on my radar......especially with all the rave reviews it gets in here. I've spent a lot of money on software this year (ughh!! that Larry!!! .............)......he's giving me gas...gas.....gas....

Wow, talk about consensus! Thanks guys!

mumpcake
I like GR5.  I feel it has improved quite a bit over GR3.
 
If you are at all interested in Amplitube, though, they are having a serious group buy going on which ends in a couple of days.

I am interested. Please post details, thanks.