Yeah, there's a prepayment of RM400 if you have not been with Maxis for more than 6 months with a minimum of RM250 per month on the bills. However, if you've been a Maxis 'loyal' customer (basically more than a year) the person in charge can waive this requirement as they have done for my case. However, they also have a right to limit your choice to a few plans to 'minimize their risks'.
Coming back to what is being offered by Maxis, I think we can see that Maxis is increasingly progressive in offering the iPhone (by introducing more plans). Especially the prepaid one time off payment which I can see is designed to knock off gray imports. But I would stick with iValue plan if you have been using Maxis. You get the phone at a lower price. Of course, some can argue that the overall cost of ownership is high, but hey... we need telephone service anyway so it doesn't really matter. By the way, 512MB is a lot to use. I've been FB-ing, chatting, email and Google Mapping (don't use satellite imagery, it uses more) as much as I can and I only hit 80MB++ with still room for youtube. Trick is, stay off the Safari browser. Use apps for accessing FB, etc they're more efficient. Use RSS to pull stuff from your favorite sites.
And for those who claim that oversea telcos offer cheap/free iPhones with an affordable monthly cap. Here's the explanations. Most of these plans offer like AUD$49, 79, etc but given credit time worth AUD$350 so on. Most people would think gee... thats a lot to use, very value for money. Wait... the per minute cost is not printed. Look at the fine prints, AUD$0.80 per minute with 30 second block. Thats like almost equivalent to our minutes (RM0.15, 30 seconds block) offered by Maxis if you would compute. The point is their per minute charges is high, Malaysia is still very competitive in the mobile communications rates. Of course we pay for the phone, but its unlock and we're free to choose our telco service. Phones from elsewhere is free but locked and you pay additional costs for unlock which is the same in the end (lets not venture into 'illegal' means).
Conclusion? Apple phones are not cheap stuff hehehehe unfortunately but they are highly desirable. If you're residing in Malaysia, just get one of Maxis's plans or you can wait for better offers.