ORIGINAL: rajul
You could try looking for a used sim in RCU marketplace at very good prices. You might be able to get the older versions such as AFP or G2. You could upgrade AFP to AFPD at a later time.
I wouldn't buy software used. IT's just not worth the risk.
To the origional question, G3 and AFPD are both good sims. I prefer G3 because it's harder and I learn how to correct the planes. It's worth way more than I paid for it IMO. FS One has been delayed so much, I don't really trust it. I think I'll wait a year or so before I consider buying it. I don't like Horizon either. You definitely want a sim with a transmitter. IF you use the keyboard commands, you might have a hard time transferring any skills to your real plane.
Hope this helps,
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