+10 CT3, its the best one out there for the type of chain you are using.

And on nasty, rusty chain that you will be tossing, my preferred tool continues to be my 24 inch bolt cutters. Broke a few chain tool pins (replacable) before I wised up and switched to bolt cutters. Harbor Freight or similar on bolt cutters. On sale right now for $14.99, be sure to download a 25% off coupon at slickdeals along with a free tool coupon. That gets the price down to $11.25. While you are there, pick up their brake hone, $6.99. Always handy to have one of those for deburring seat tubes and steering tubes.