I have the Clifford Concept 650 in the Supra for 13 years , no issues , I reckon alot is got to do with the installation alright
I would try MDS Ireland (Irish Clifford Dealer) , he installed in my Golf, 13 years ago , alarm only started giving me issues this year , but good service off Brendan, Ghost alarm seems to be the one to go for these days , not too sure if just for canbus
https://www.facebook.com/MDSIRELAND/
Gary Ward heard very good things about , GW Autos car alarms, the flavour back in the day was the K9 Alarm, Gary installed in alot of 90's Japs back then
https://www.facebook.com/people/Gary...00004305763648