Lift Choices

This is not my first truck by any means but it will be my first lift. Have been doing a lot of reading on the subject here and elsewhere on the web but I'm not 100% sure I have everything down. Based on my research, I'm pretty set on a 6" lift and I've narrowed it down to the following three kits but I was hoping that someone that has experience with them could pipe in with their opinions of the pros and cons. Just about any insight would be appreciated

Fabtech K7019 ~$1600

• 6" Basic System
• Use 315/70R17 tires w/ 17x8 wheels w/ 4 5/8" BS w/ minor trimming
• 1 FTS26026BK Component Box 1
• 1 FTS26007BK Componet Box 2
• 1 FTS26010BK Spacer Box
• 2 FTS7181 Performance Rear Shocks

Pro Comp K5073B ~$1600

• Lift Height: 6 Inches
• Front Lift: Drop Crossmember,Strut Spacers & Steering Knuckles
• Includes: Differential Drop Brackets, Sway Bar Drop Brackets
• Rear Lift: Block/U-Bolt Kit with Add-A-Leafs
• Shocks: Rear ES9000 Shocks
• Shock Boots Included
• Max Tire Size: 35X12.50
• Wheel Size Range (Inches):18+Wheel Width Range (Inches):8-9
• Min-Max Backspace (Inches)4.0-4.65

Also, how much of a difference would the following kit be compared to the two listed above and is it really worth the additional thousand dollars?

Pro Comp K5073BMX ~$2600

• Lift Height: 6 Inches
• Front Lift: Drop Crossmember, Steering Knuckles & Coil Overs
• Includes: Differential Drop Brackets, Sway Bar Drop Brackets
• Rear Lift: Block/U-Bolt Kit with Add-A-Leafs
• Shocks: Rear MX6 Shocks
• Shock Boots Not Included
• Max Tire Size: 35X12.50
• Wheel Size Range (Inches):18+Wheel Width Range (Inches):8-9
• Min-Max Backspace (Inches)4.0-4.65