I think any XBLCG that puts itself in the 800 mspoints category immediately gets compared to the best XBLA games, and rightfully so.
I'm sometimes, but not often, willing to spend a little extra for more value, and I understand the need to recoup costs of development.
But no achievements is going to be the biggest complaint by a lot of core gamers.
So we need to feel as if we are getting compensated for the lack of achievements.
Hence, cheaper games that we can buy on impulse, rather than having to consider if we are getting our money's worth at $10.
Good Luck everybody!