On my search for the smoothest ballpoint pen, I stumbled upon a forum in which users recommended the Pilot Axiom. This pen usually retails anywhere between $15 and $20, which isn't bad for what you get. It comes in five color options: Black, Matte Black, Cherry Red, Cobalt Blue, and Pearl White.
The Axiom comes loaded with a blue medium point Pilot Dr. Grip Center of Gravity refill, which is extremely smooth and reliable. I have been using the Axiom in my daily rotation for about two months and it is quite smooth with absolutely no scratching. Maybe its because I typically use rollerballs and fountain pens, but the performance of the refill really surprised me.
The pen itself is heavier and fits extremely well in the hand. I believe the weight makes it easier to use with minimal fatigue, especially during long periods of use. The barrel is solid and not slippery due to the "grip dots," which are slightly textured to help you grip the pen. The clip is sturdy and will not bend over time if used gently. The Axiom includes a circular opening on the clicker, which lets you know if the point is deployed; blue for retracted and black for deployed. This is a great feature for those who carry the pen in their pocket.
The Pilot Axiom is great for someone who wants a quality pen, but doesn't want to break the bank. It is extremely economical with refills costing as little as $3.69 for a pack of two. This is definitely one of my favorite EDC writing instruments!