45 psi sound high. I'm doing soda water at 30 psi, which is common for soda from what I've been able to find. Temp is set at 40 degrees F. I use 25 ft of 3/16" line for the soda water. It works well. It takes at least a week to carbonate after I start it with LOTS of shaking under pressure to get the CO2 absorption off to a good beginning.
It stays carbonated pretty well after "bottling" but the pressure can sure build up if it gets warm. As others have said, be very sure you use containers that can take the pressure. I've found they maintain carbonation best if you leave minimal air space when filling, start cold, and keep them cold.
Your mileage my vary, of course.