@LiveLean, I'm sorry to hear about your car crash.
What would you have done if you had received these same injuries due to something that was nobody's fault but your own? Suppose instead of the underinsured motorist hitting you, you hit a patch of black ice and skidded into a light pole or something.
Not having anyone to blame but yourself and mother nature, the cost of treating your injuries would have needed to go through health insurance. Yes, you would have likely paid more out of pocket for medical care than you did with underinsured motorist insurance. You would have used your disability insurance (if you had any) to pay your bills during any time away from work, instead of having these expenses covered by your underinsured motorist coverage.
We buy insurance to protect us from financial ruin when something bad happens. Getting hit by an underinsured motorist can definitely cost a bundle of money without insurance, but what I don't like about this coverage is that it is so narrowly tailored to one particular situation. You're protected from that one thing, but why protect yourself more from that thing than from crashing your own car, getting in a skiing accident, or injuring yourself in any number of other possible ways?
By purchasing different levels of insurance for different ways of injuring yourself, one of two things must be true. Either
1) You have too much insurance for the things you're more protected against; you could accept less (or no) special coverage for those things and still not experience financial ruin when they happen, or
2) You have too little insurance for the things you're less protected against; getting injured in these ways would still result in financial ruin.
I'm not saying to skip all insurance. Everyone should have good health insurance, covering a full range of treatments for potential illnesses and injuries, with low enough out-of-pocket costs that you can actually afford to pay them when necessary. Everyone who still relies on their income from a job to support their lifestyle should have disability insurance to help pay their bills in case of any disabling injury or illness that keeps them away from work. Everyone who has any significant amount of assets should have strong liability insurance, likely an umbrella policy and any professional liability insurance that may apply to their work.
If you have all these broad-based policies that protect you from financial ruin without regard to the specific event that triggers it, why add extra insurance for just one way of getting hurt?