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With such a short focal length collimation will be pretty crucial. For me, I know the collimation is quite good when I can see four minor diffraction spikes in between the four main spikes on a star image. The comment about the laser being wrong is right imo - lasers are great for big truss tube scopes where offest can actually be measured and you can see your secondary mirror in the open tube. But for a closed tube give me a sight tube and cheshire anyday.
The coma is more likely a combination of the very fast mirror and the eyepieces together and there isn't much to be done about that. (Its a funny thing, I've met people who can't stand any coma anywhere in the field of view, yet others are quite happy to have heaps around the edge as long as the centre of the field gives a sharp view). The eyepieces that come with the scope are not the best on the market - it is amazing what a good eyepiece can do to a mediocre telescope! This is not to say you should rush out and buy new ones, just dont expect too much from you have.
Local seeing conditions are probably also a factor, especially if you are viewing from the city and have lots of sources of heat around you.
If at all possible take a look through someone elses scope and compare.
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