Their website appears to be a bit out of date actually. All powertuners come with the wideband input now for the $399 price and they are open for all GM V6 (3100, 3400, 3800) '97-05, this is new as of the latest release of the program.
I got mine used thats why it was $360, but that was back when one with the input and all that was $499. I have seen used ones on clubgp for $300 numerous times so you could try just keeping an eye out there for them. But buying one new for $399 is a lot less hassle and then you get the support directly from DHP and access to the powertuner forum and all that. If you buy used you have to rely on the old owner of the powertuner to turn over their user name/password to you with the tuner.
The HP tuners isn't that much more expensive if you're only gonna do like 1-2 cars, its just that it costs you X amount per car, and thats what would've gotten me.
1990 Maroon Grand Prix STE McLaren 3.1 Intercooled Turbo, 14.695 @ 94.49 on 12psi before cam/heads/etc.
1990 Bright Red Grand Prix McLaren 3.1 Intercooled Turbo, 14.819 @ 92.72, 189whp
1999 Grand Prix GT 9.75:1|K&N|160 tstat|No Ubend/Cat/Res|UD Pulleys|Ported M90/TB/Heads|XPZ|2.55"|Pacesetters|Stage 2 I/C. 12.442 @ 112.78
2000 Blue Bonneville SSEi Supercharged Gutted Airbox|K&N|3.4"|1.9'*|WP Pulley|Custom DHP|180*stat|41932'*|No Cat. 14.681 @ 94.80
2002 Dark Cherry Grand Prix GTP Supercharged & Intercooled
12.084 @ 114.38 w/1.743 60', 315.6whp, Fastest Stock Cam M90 GTP!
NOW XP CAMMED, 340.6whp with XP, stock heads, Gen 3 M90, 11.984 @ 115.84 w/1.750 60'!
Most HP Stock Heads Gen 3 M90 GTP!
2004 Red Monte SS Supercharged K&N|3.4 Pulley|1.9'*|180*stat|41919 plugs|3" dp|No cat/ubend|DHP|Shift Kit. 14.2 @ 98
GOT BOOST??? Friends dont let friends drive stock!