First spark plug change on my recent 1gen Sequoia

Recently I purchased a 2006 Sequoia with 307k highway miles. I've replaced all the fluids, Timming kit, and spark plugs. I took out the plugs with an unknown how many miles on them. I was wondering if this forum could tell by the plugs the condition of the engine. Just for note when I bought it had and exhaust leak and a bad upstream of sensor. All the plugs looked the same. Here is pictures of the plugs. It now has 310k miles no noticeable oil usage and oil looks clean.