I've been running Brenspeed tunes for over 40,000 miles now, and they are spot on (even a local dyno tuner couldn't improve it).
Yes, Steeda and Bama do have free tunes for life programs, and yes, both companies are great to work with. American Muscle is a go-to for tons of things, but I personally won't choose them for my tuning. I've seen too many people have issues with pinging, throttle hesitation, and idle surging to put them as my top choice; however, they are still a fantastic company.
When you order your programmer from Brenspeed (I'd suggest a JLT CAI/SCT X4 combo), you'll have to fill out a form with all of your information from modifications and car's computer code to tire revolutions per mile and axle ratios, so you shouldn't need another tune unless you add modifications down the road. Brenspeed is so competitively priced in most aspects that I just buy most parts from them and take the free tuning; however, I was looking at buying a set of JBA long tube headers and a FRPP intake manifold from Craigslist last year. I called Brenspeed and informed them on my situation and planned parts to add. When I asked Brent what it would cost for a new tune, he told me nothing for the long tubes and about $25 to reprogram for the CMDP delete of the intake manifold.
Therefore, don't let the no free tunes for life (unless you buy from them) deter you. They're likely the best canned tunes in the business, and they're not any more expensive than the competitors for retunes.
2007 Mustang GT 302 stroker 6060 swap, 3.73 gears, Hidden Hitch Receiver, Barton Short Throw, JBA LTs, Borla Touring Axle Back, Lito tuned SCT X4. BMR SP009, Bilsteins, J&M CC plates, J&M LCAs. 4 Piston Brembos
DOB GT450 with VMP Gen II 2.3 TVS | 13/14 GT500 HE & IWP | GT500 hat & DW340s | FRPP 52lb | CMS Stage 2 Blower Cams | Comp 113 Springs & Retainers | 8 rib conversion | Track Spec GT500 Vents | PTFE Heat Barriers