Alarm sensor type recommendations

[mojoman]

I'm installing a pager type alarm, want to try to keep it simple as possible. What types of sensors would you recommend. I don't plan on using the remote start and other features, just an alert if the van in being tampered with or broken into. Would like to keep the motion vibration and one other sensor. We don't live in a problem area and it will generally be used while staying at a time share or hotel or when shopping.
Any suggestions from past experiances on the types sensors to get or avoid?

[hbn7hj]

My bias is to only use a sensor that shows a door open with the alarm siren inside. Door sensors are not prone to false alarms and the inside siren will stop someone's entry. You will have door or window damage but nothing more.