I've lost two magnetic soft tank bags but both times were my fault. I left a gas station stop with the bags lying on the seat behind me. Other than that I've never had any trouble with theft or vandalism on many trips both close and far from home. Some common sense is involved like choice of location and covering up but mostly I've relied on the general goodness of people. It works for me, YMMV.
If being able to go now or go out further and longer was based on the cost of soft bags vs hard luggage I advise to go now with what you have or can afford now, and can afford to lose.
This will make sense to some and might offend others................. Do you own your stuff or does your stuff own you?