Power meter or Tacx Vortex Smart

I currently use a Tacx Blue Motion with Garmin speed and cadence sensors.  I am looking to upgrade my setup either with a Tacx Vortex or Power Meter and wonder what people would advise as being the best option to upgrade.  Unfortunately I only currently have funds for one or the other but my thinking was to go with a power meter as I could use this training both inside and outside.

 

 Thanks 

I’d always advocate for a power meter over a smart trainer if the decision is either/or. Power meter can do the job indoors or out. Smart trainer cannot.

just remember… you can’t race with your trainer… but you can use a powermeter on a trainer and outdoors

 

If it is your budget go for both.  I use the Vortex Smart with a Powertap C1 meter.  Power meter is much more accurate than the Vortex Smart.  Vortex Smart or any other controllable trainer, does make for a great riding experience (as opposed to a classic trainer).  I found that the Vortex Smart was accurate in certain power zones but could be way off in others - it was pretty consistent about this.  It is also very sensitive to the contact pressure between tire and roller; power meter takes this out of the equation.