Dyno Software

I'm not really sure where to post this but. . .I'm thinking of buying some kind of dyno software for my PC to give me a good idea of what to expect for my next engine build up. I know that only true way to tell the power output of the engine is to actually go have it dyno'd on a machine. I just need something to let me build a concept of what i'm looking for, and also learn from it. I was wondering if anybody here have used any thing they like and what would you recommend? Here are a couple that i'm considering just to name a few :

Dyno Sim

Virtual Engine Dyno 2005

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