Personally i would go with the Supercharger cause the boost is much easier to manage then the turbo and re=tune during the colder season. Running the Typhoon has it's ups and down with the different seasons, but the trubo chargers do make more boost then the supercharges and faster if the set up is right, but one bad detonation will put your Sierra out of commission till you get it replaced.
If your just looking for a friendly bolt on kit, try these guy's and feel free to call Al. He'll be more then happy to answer you any questions you may have. http://www.wynjammer.com/
If you would like to go with turbo charging your Sierra, contact these guys and they will be more then happy to answer any questions you may have and they do have a Kit for the Yukon/Tahoe and Escalade. Its more a preference that any other thing and how much tuning you would like to do throughout the year. http://www.cartuning.ca/
If you want to keep it simple and keep your boost to around 6 PSI to no more then 8 PSI of boost then your not going to have to tune it as much as you would if the boost is high. Nothing like having a tubo/supercharged truck, there like a really good G/F. Always puts out but expansive and always needs your attention. LOL