I've got the HK$ TT Type-1 and really like it. It took no time at all to install, and works well. It can read MPH, RPM, Volts. It has a peak memory as well as alert alarms for the various read outs. It has two adjustable turbo countdown timers as well as a full auto one. But you have to run an rpm signal in to use that feature. Over all it is loaded with gadgets, which is probably why i bought it. If all you need is a basic turbo timer then it may be a little overkill.