I haven't gotten one yet, but I'd definitely say it's a worthwhile investment. Check out some threads in the tuning sub-forum, and you'll see a lot of satisfied customers. I'm planning on getting mine once I drop my new engine in, hopefully next month.
if you have patience, the tweecer is an awesome tool. for anything beyond basic stuff (fan settings, timing, injector size, etc.) the learning curve is steep and the documentation leaves much to be desired. if you want an easy solution that requires minimal effort, the tweecer is not for you. however, if you want full control and dont mind spending time researching what things do, then go for it.
I am interested in learning about the EEC and I do not want a quick fix. I just want to know if it is worth it to get it NOW or should I wait until I do more mods?
This is the best time to get the TwEECer! Get it early and become comfortable with it. Do little tweecs here and there. That way when you start getting into the more detailed things, you won't be intimidated.
A lot of peeps get discouraged, IMO, because they do these great hot rod mods then realize they have to tune them! But tuning a hot rodded engine is MUCH harder then a stock one. Get the TwEECer now and gain confidence with it, that way when you start getting into more serious mods, you can approach self-tuning with excitement rather then dread.
I waited until my car would hardly run without one, before I went and purchased one, and it was a bit of a learning curve, while my car sat in the garage. i still haven't learned 1/2 of what this thing can do, but it is awesome. If you are planning for more mods in the future, it might be a nice thing to get now and learn, while your car can still run without it