I've sat in both cockpits (not as a pilot, but a fanboy.) There is no comparison. Not only is the Viper's canopy better, but its seating position is much higher relative to the frame of the cockpit. The glass comes all the way down to your knees. The Viper's cockpit is also tighter, which may be more uncomfortable for longer periods, but you feel more connected to the plane, like you're fused with the machine.
This isn't really a knock against the Thunder though, because almost no other fighter can compete with the Viper in this arena. The Raptor is probably the only fighter that has a better cockpit view and feel. There is a downside to this type of cockpit design though: I've heard that at high mach the Viper's cockpit gets super hot because of the air friction on the glass.