I believe the RE10, RE15 and RE16 are similar mics. The RE16 is still in production. They are nice smooth midrangy mics that are forgiving off axis with minimal proximity effect. The off axis forgiveness is what they are designed for. The 635A omni, also still in production, used to be seen a lot as an interview and TV production mic. In fact, I used to see all these mics along with the RE20 a lot on TV in the 70s and 80s on Country Music Nashville based TV, such as Hee Haw and Pop Goes the Country. They are great old mics, but every time I see one for sale of late, they seem overpriced. Sam Ash and Guitar Center in Nashville have put prices upward of $200 on used RE16s and 15s. Seems excessive to me, but I'm no expert. I do own two RE15s, two RE16s, and two 635s...all old and well worn. I love them for banjo, harmonica, mandolin, or anything too bright that needs to be smoothed out a little.