I agree with waiting for a few sets of leaves, the plants would be stronger and able to get a better footing in the ground. If not, Your plants could be susceptible to harm easily from slugs, cutworms or other leaf eating insects.
When you do plant out set your plants slightly deeper. You do have the right idea, wait until the evening temps stay around 50 deg or above. I see alot of anxious folks here that live in the same Zone (5a,b) range
that I do and are already pushing their plants outside. Sure they may survive evening temps in the 40's but how will that effect their growth through the season. I have no problem waiting until the middle to end of May......after the last hard frost date. Never had a problem when doing it that way. Planting to early when the soil temps cooler and the occasional down pour of the spring rains, sometimes for a few days can create havoc with pepper plants. Fungal and Bacterial issues can result from the soil, not mentioning the chance for root rot.
You'll certainly have more people answering your question with their ideas and opinions. For what its worth read them all and evaluate the situation.
Good luck with your seedlings, warmer weather right around the corner
Greg