Hard to say whether or not you'll be impressed, because I don't what you expect. I found this site semi-useful before I bought anything.
http://www.astronomics.com/main/cate...JS5VDJ5/Page/1
I have peered through the smaller 76mm version and did see Saturn's rings and one of its Moons, not crystal clear like the images on the website though. Our Moon will look quite impressive through it. They reckon (whoever they are) that you may magnify up to the scope's diameter (in mm) times 2. Theoretically this means you'll be able to push it to 200x, but it'd be safer to expect half of that, about 100x. I'd be a cold day in hell before you get an image like the one on the above website at 200x through the 450. Incidentally, I gather that 450 refers to four and a half inches, not 450mm. 450mm is a BIG scope. Hope that helps. Good luck.