Few points here:
According to the police most thiefes will just grab your bike and put it in a van - your alarm will be useless.
[url=https://rideapart.com/articles/ask-a-motorcycle-thief]https://rideapart.com/articles/ask-a-motorcycle-thief[/url]
There is no 100% security.
You need to decide which thiefes you want to stop and how based on where you plan to leave the bike.
1. Option 1 petty thiefes/joy riders - good alarmed disc lock is enough - like Xena.
2. Dumb carrer criminals with vans - you need a chain. These are the guys that want to break your Fazer for parts. The alarm is completely useles here.
For a good security you need decent chain with a good lock. The best ones are
Almax and
Pragmasis.
The problem with good chains - they are heavy. The best security for bike is 16mm chain. You need a topbox and carying the beast is pain. Realistically you need 1.5m chain - that means 4.5kg/m X 1.5m = 6.75kg add to that at least 1kg good lock and presto about 10kg heavy equipment in your top box. And it will cost you about £160.
You can compromise with decent 13/14mm but these can be broken. The level of protection will cover only some thiefes with 14mm chain.
3. The clever scumbags - bad news they can wireup most alarms in 30 seconds and will crash any chain with hydravlic blot cutter in a matter of seconds too. Good news they operate mainly in big town areas like London and are NOT after our Fazers. They are after 20k super bikes mostly. Thank God for that
Also bare in mind there is no such thing as decent cheap alarm. The cheap ones or even the expensive ones have reliability problems. I have had issues in the past with alarms.
Choose your alarm model than google it for failure - you'll see what I mean. You do not want that crap on your bike.
Alarms do make some sense for cars.
Based on the points above alarms are useless for bikes. I have decided for myself that having an insurance and simple
Xena XX14 alarm disc lock on the rear wheel is enough for me.
Just do not forget to use steering lock and plan your trips and parking places.
My 2p.