Ignoring the premiums for a moment, the plans are equivalent as long as you need less than $5,500 of treatment. Between $5,500 and $14,000 of costs, plan 1 is better because the lower deductible plus 10% coinsurance is still a lower total cost. Past $14,000 of costs, Plan 2 is better.
Now consider that Plan 1 has premiums that are $10/month less than Plan 2. That changes the math a bit. Now, you're $120/year better off with Plan 1 if you need less than $5,500 of treatment, and the break-even point moves out to $15,200.
Add in the fact that Plan 1 makes you eligible for an HSA and Plan 1 starts to look even better. An HSA is an even better savings vehicle than an IRA because the money is untaxed both on the way in and on the way out, so you should max this out before your IRA if you have to choose.
All of this supposes that the medical expenses are really an apples-to-apples comparison between the two plans. If Plan 2 offers a better set of available doctors, or has negotiated better rates with the doctors and hospitals you're more likely to visit, or is more willing to pay out claims with minimal hassle, you may well find Plan 2 to be a better deal overall. These things are remarkably hard to find out before choosing a plan.
