Realiability goes to DEI for just about any unit they sell. If you want something worth spending your money on, then go with a 2-way Responder Sytem. Like the Viper 791xV of Clifford Matrix 3.5 equivilent.
Another good unit is the Copusa 2WSS, great range.
THough, this units an go above the 400$ mark for a quality install if you are looking to get it installed.