One day of sexcapades will not be a good judge of character. If you want to know someone's behaviour, stay with them long enough until they are comfortable enough to put down their 'armour' and reveal their true nature.
Not true c kila mtu akona hasira meru. Most probably it's stereotyping although it also depends on where you are specifically in Meru. You could get very peaceful people or the worst depends on where you are. Best advice know your way around like don't trespass shamba ya miraa in Tigania or Egembe coz that's the first you can do there. But truth be said it's just like any other place in kenya