Wait until you break something and it costs you $5,000.
Can't go wrong with SCT and Innovative. I have MBRP and they've been great, except they rusted in 2 years (and I bought the ones guaranteed to never rust) but MBRP stood by their warranty and replaced them free.
Gauges - I'm a fan of the analog variety on my pillar. Some like the electronic ones more. Guess that's personal preference.
Buy yourself a set of head studs when you get the chance, and look into an EGR delete. Both of those combine to make your truck much more reliable (although illegal with the EGR delete). I'd also consider buying an intake elbow with pre-tapped nodes for attaching a PSI gauge or potentially injecting NOS/meth/water.