Chinese projectors are starting to become interesting right now, but the one you linked it is not a good example of that. Search for Unic uc40, it has a decent relation between price and specs and it is actually worthy
Looks like this situation has changed. There is a new emulator in town based in freedo and 4do for Linux that is coded in C and uses SDL. It is all about portability. You can read the whole story (and visit this guy's source) here:
I have been thinking about the price thing and since in this post you are more or less looking for opinions, here comes mine.
I think the price is too much. Maybe not for the amount of work involved and maybe not for the american market, but think about China, for example, you could have a big niche market there but not with a pricetag of 8 dollars. Instead your app is going to be massively pirated, that goes without saying.
Another thing you are going to face is the tidal wave of emulation noobs, with comments like: WHERE R DA ROOMS give my money back this app is xxxx. In my opinion the amount of these nasty comments is going to be directly proportional to the amount of dollars needed to buy the app. Maybe you can control and answer those in english (or pseudoenglish), but every buyer is welcomed in Google Play with comments in his own language.
If you take a look at the emulators that are doing big time in Android, you realize that most of them have a support forum where users are helped and the author takes care of the problems that appear. That is part of the price they charge, no doubt.
Maybe you could launch it at an special price, something near 1 dollar, and this way help building a community of happy users, letting them spread its virtues. When you have a good base of users, a well established support forum and a reputation you could raise the price.
I am sure you have taken a look at who and how is making money out of this Android thing, but i think you could try another approach to get the money you, no doubt about this, deserve.