Picking a power meter for the track is more about avoiding features that will annoy the hell out of you than it is buying some "killer feature".
Easy swapping from bike to bike is a killer feature.
Left and right power measurement is a killer feature.
Don't buy those if they come with a deal-breaker like taking 3-8 seconds to wake up. Missing 8 seconds of a standing start effort is a lot...even if it's a pursuit effort. The start is very important. Most new racers screw up and go out too hard. This will show up in the first 8 seconds.
In my opinion, the "Gold Standard" power meter is the WIRED SRM Power Meter using the PowerControl 5 wired head unit.
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OK the "Super Gold Standard" is the SRM Wired Scientific model, but that's super hard to get and super expensive.