This is a big debate are for its of people but overall you will do better getting a programmer that is custom configured for your truck than a "one-size-fits-all" type of programmer. Something like what is offered by DP Tuners, Beans Diesel, PHP, etc. is what I'd be looking at. Personally I have been very happy and impressed with DP Tuners. You'll be surprised (read "grinning") at the performance lying dormant in these motors that a good tuner can wake up into live tooth bearing action :-) Regardless of how you go an EGT gauge is the bare minimum and practically speaking really needed gauge. The others are nice to have to monitor things but the EGT gauge is what you'll be driving by to keep from harming your motor. Depending upon what you do in mods to your motor will help you decide what kind of tunes you'll want to ask for. An 80HP daily driver tune is more than enough for most folks with an unmodified motor. You can always change the tunes as you do more to your motor.
Early 99 F350 4X4 CC 7.3 Auto. A.R.E. Topper, bed carpet/bench inserts, Rhino grill guard, AIS w/sleeve, Fuel filler mod, GOS headlight harness, 02-04 Headlights, Rancho HD stabilizer, 06 Telescoping/heated mirrors with C-Btr Mirrors, Hella FF1000, Htr Bypass valve, front receiver hitch, Quadzilla XZT gauges, ITP Pre-pump/In-tank mods, Pioneer P5000UB w/XM radio, 4 Infinity Kappa 682.7cf, Fumoto valve, FIAMM Highway blaster horns, SS HPX, IDM mod, DP F5 (Stock,Drive-thru,60T,80E,120,80E-Mountain,1200), Walker BTM, RR, Dieselsite BRV, BTS Tranny (2nd one :-), 31 row tranny cooler, Bilstein shocks, Amsoil bypass oil filter, Stancor HD Glow Plug Relay, billet thermostat housing, front & rear parking cameras, Aux reverse lights, Heated Seats.
Security: CrimeGuard Alarm with remote notification, DIY jimmi-jammers, door cylinder locks and linkage removed, padlocked rear bench seat hinge, PCM, DIY "pitstop" switch.