Is it sufficient RM6500/Month - Penang ???

I disagree. I have been living in Bukit Mertajam for 3+ years and dont see the downsides you are talking about. Mainland is far cheaper for living expenses and island activities are always accessible. Example, I live in a 2000sqft terrace house, half furnished, 4-aircon, finished kitchen, quiet and clean 99% middle-class chinese neighborhood, walking possible to shopping like Tesco and Jusco, RM700. Previously when i asked an agent, more than one, on the island for such an animal, they laughed so hard it hurt my ears.

As for pollution, Im not sure what you mean. On the Island, there is endless talk about factories east of the airport which are openly dumping toxic waste right out their back door and nobody does anything about it despite its against the law. That waste goes straight into the ground and water supply, not to mention rivers and then into the ocean. Thats not to say the mainland would not have similar problems but local papers and general chat seems to focus on island problems and I have not personally seen any piles of waste, toxic or otherwise, in my general area which also has no factories around.

As I read posts around the forum, i would think the average expat would be happier on the island where there would be higher concentrations of other expats--but it comes at a price. Ive only seen a few around here in the past 3 years and I choose to be with locals so thats OK with me. Where I live is more like a quiet life, not an electrified night life many expats enjoy.

As for competition among chinese to lower prices, what I have seen since 2000 is price-fixing at the highest levels possible. "oh he raised his price! ok I match him! we all benefit!" I only have seen undercutting of prices when a new guy moves in and temporarily cuts to drive out competitors who do not wish to lower prices and when they have cleared out he raises his prices.

The "petaling street" rental syndrome is also prevalent here. One person rents many shops and spaces and sublets at HIS prices. Also, its not unusual to find one family owning many shops in the same area to control prices of those items on THEIR terms. I happen to know one family who owns 27 phone shops in Penang. Different names, staffs, appearances, same owner, same prices. They do that in the restaurant business too. Thats not competition, thats monopolization and price-fixing which is not yet illegal here. One day.

In any case, I as one expat am happy on the mainland. I go to the island whenever I want, without a higher fixed living cost. So, for people trying to save money I can say its better on the mainland. If a more hustle-bustle life among other expats is important and price is not too much an issue, the island is better.