Dig some geographic info about M residence spot last friday when i went there.
Flood issues?
From Google Earth, the land over there was actually slightly higher, compare to kundang jaya area. Asked a local people who live at saujana rawang, according to him, no flood was occurred before in this 2-3 years. But There is a small river nearby which connects to Kundang.
Pollutions?
If you drive along Rawang town, u'll find alot of factories and heavy vehicles(lorry ,bus etc.), but once reach Bandar Baru Rawang, the air gets better. Drive along jalan batu arang and you'll found the air turns out nice after u pass by taman velox, went down the spot and breath, no smell and air is fresh. However opposite road there's a small factory in 2-3 KM away
G&G?
No confirmed answer from dev but what they promised was a guardhouse at each entrance and 24 hour guarding and night patrolling. RM120 yearly for Clubhouse Fees and Neighborhood security. For those who worried so much about G&G issues, just waited a few month till it launch and make your decision, round Feb/March 2012.
Crimes?
There is no place on M-Land that has 0 crime record. Bandar Country Homes and Saujana Rawang have few cases, so does taman velox and bandar tasik puteri. The best thing that a house developer can do is to reduce the chances to its lowest. Restricting the residence area from public access. Whether the guards will do their job well in future, we can only judge based on past projects of Mah Sing.
Will M Residence become like Setia Alam? No one can be sure, but having a Large Jusco Aeon Mall nearby is always pointing to a bright future. Examples are Bukit Tinggi, Cheras Selatan (Balakong), and Equine Park..

And from Mah Sing's past projects, i can say i believe in their QC part. Just look at Kinrara residence, Garden Residence, M City...non of them turn out to be BAD....
Just my 2 cents