I am a long time TrackIR user and have had the Oculus Rift since the summer sale this year. As others have said, the 1:1 tracking and feeling of being inside the cockpit makes VR amazing. But the resolution is so low due to the wide field of view that it feels like playing at 800x600 on a large TV. Also, as wide as the field of view is, it still feels like you are looking through a paper towel roll.
Aces High is one of a few sims where VR has been implemented in a way where it is practical despite the resolution. If you are going to play Aces High and can afford VR, its advantages far outweigh its limitations. It is the combination of smooth, precise 1:1 head tracking and a wide field of view that beats the pants off flying with a normal monitor and TrackIR.
However, if you are tight on money, VR + acceptable GPU is a lot more than TrackIR + acceptable GPU. Unfortunately, GPU prices have been inflated for awhile. I got a deal on a GTX 1080 a while back: $470 after a $30 rebate. That's not cheap (it is the most I have ever spent on a gpu), but right now, you are lucky to get a GTX 1070 for that price. To enjoy VR, you need smooth high frame rates and some pixel pushing power to smooth the image to make up for the pixels per degree of view. I don't know if I would enjoy it as much if I had anything less than a GTX 1080 (though I understand the GTX 1070 is supposed to be ok). I would get a 1080 Ti if I could afford it.
Another factor in going with an Oculus Rift is the PC needs three USB 3 ports for the head unit and two sensors as well as an HDMI output for the head unit. My two PCs have at least two USB 3 ports on the back and two USB 3 ports on the front, which is just enough for my purposes (I have all my USB controls connected to a USB 3 hub).
Aside from the cost of a powerful GPU, VR is in many ways a better buy than TrackIR. When you buy an Oculus Rift with the touch controllers for $400 (it was on sale for $350 over Christmas!), you are getting a very high resolution dual display with a head tracking system way better than TrackIR, two sensors (one of the reasons the tracking is better), two controllers, and the software to tie it all together. What this tells me is that TrackIR had a virtual monopoly and therefore was able to put quite a profit margin into their pricing. It also tells me that demand for the Oculus Rift wasn't as high as hoped for and was facing serious competition since their price rolled down so much so fast.
Hopefully, competition and tech advances will continue to reduce the costs of VR and increase the quality. The real limit is cpu/gpu throughput so that the resolution can be drastically improved. But for now, if you have a tight budget, a TrackIR and a GTX 1060 is a lot cheaper than a VR setup and a GTX 1070/1080.
Looking at current gpu pricing/availability, it has only gotten worse! Everything is sold out or selling for over $900. Bitcoin mining needs to go away