The old Ebonite Matrix TPS III is a great example of this. I found one relatively cheap on eBay. With the coverstock being a fairly dull particle you would expect it roll through some oil and have a tame backend, right? Well instead I get a lot of length and a very strong backend even with a 1200 grit finish on a typical medium oil THS. Actually the ball goes too long and turns too hard even on that sometimes. When the lanes dry up and I need to move in the recovery is great.
The old Storm El Nino also surprise me. Being that it is a late 1990's reactive, I thought it would replace my old, damaged Brunswick Danger Zone. It turns out I got a LOT more ball than I bargained for. It actually hooks more than most balls today outside of the high performance stuff. Good ball but needs some oil even when it is polished.
In more recent times, the Hammer Gauntlet gives me a surprisingly smooth look. I thought the ball would react strongly to friction but instead I get a very soft but sweeping hook.
What balls have any of you guys had which gave you a surprising look but you still liked?