How likely are you to use your plan? The lowered deductible doesn't mean anything if you aren't going to go to a doctor/hospital/etc. For this plan to be better, you would have to use $300 worth of extra claims for it to be worth it.

Remember that certain things like an annual physical are generally going to be covered 100% and aren't going to hit your deductible, so the $300 would have to be other claims.