It depends on if you are able to put reasorces into both or only one. If only one, then wait, if you can use some more resources, you can go for standard Gauss. Priming of Warframe is really minor statwise so it’s mostly cosmetic addition. Also In the next patch there will be added Gauss Deluxe skin.
Wisp Prime should likely come in the span of three weeks from Kullervo update that was teased to release this month (and I wouldn’t be surpriced if she released only after few days from update release)
And not full of bots like Reddit as a whole.