I know this is an older topic but I just came across it and what the OP wants to do is fairly easy with a solution that hasn't been mentioned yet.
Alright, so definitions of "gust" aside, the goal here seems to be to log max/peak wind. To do this I would recommend going to with an ultrasonic anemometer like the ResponseOne 91000 from Young. I'm 100% sure there are other suitable makes/models out there but I *know* this model will work for this application.
With the 9100 you can set it to continuously output the readings every X milliseconds via RS-232 or RS-485. I've tested the similar Young 92000 down to 200ms. Most dataloggers including WeeWx on Raspberry Pi, store data as archive records every x minutes and record the low, high, and average value for the archive period as well as the timestamp for those values (low/high/average). You won't have to worry about large amounts of data being stored.
BTW, if you do decide to go the voltage output anemometer route, keep in mind that there will be a voltage loss between the anemometer and the datalogger. That voltage loss will vary based on the temperature. I tend to avoid those units when peak readings are important.