Aftermarket alarm vs Toyota factory alarm, Which is better? Options

[CoSo]

Ok, so I have a Toyota Factory Alarm that came with the Celica. It's the one with the valet mode as well as motion sensing radar detection. I'm quite satisfied with the alarm, the motion sensing thing is pretty cool .

Recently, my remote has broken down and won't send a signal to the car (it's not the battery but the connection itself I think). I was quoted, at best, $140 Aus to replace and recode the OEM factory remote from Toyota.

$140 seems quite steep for a bit of plastic and wires, so I was thinking that maybe it would be better to get an aftermarket alarm installed, however I'm not sure which one and whether it is worth it or not. Obviously if I do go that route I'd be willing to spend a decent amount if its worth the money. Any suggestions?