Obviously there are advantages to buying a hardtail over a full suspension and vice versa

a few things to think about: once upon a time, there was NO suspension on bikes and people rode just fine. then front suspension came out then full, then it seems a lot of people are going back to hard tails or even rigid, partly for the simplicity, and partly because of loss of power in certain sections.

Another option would be buying a 29-er , a bike with 29 inch wheels. Because of the bigger wheels you can even get away with a rigid because they act a bit like suspension BUT 29ers are a bit hairier in some technical sections and you need to learn the handling of the bike.

Budget - buying a 25 pound bike can get very pricey very quickly. So set your budget and research within that limit.

Upgrading, with in your budget you can get a "cheaper bike" that might have some good things about it and then upgrade handlebars, seat post or wheels to make it lighter.

Personally I like the hard tail, even on technical because i feel i have more control over the bike, plus the simplicity, i don't like having all these little "parts" that need to be fixed regularly.

Another thing to think about is your riding style, and racing. If you plan on doing "regular" cross country races, investing in a lighter bike would be good. But if you plan on doing longer 8 or 24 hour races then a full suspension is definitely nicer on the body. when i did my 24 hour race i was very happy to have the full, but now i am back to the provincial cup circuit and i am riding the hardtail which is better to climb with (which there is lots).

Will the bike let you test ride the bike you are interested in? That's probably the best option. Test ride one versus the other and see which you like. because there is also the geomtry to think about, yes maybe you want to go with the lighter bike but if it doesn't "feel right" then it might not be the right bike for you.

anyway just throwing some thoughts your way...let us know what bike you are thinking of thinking about...

Han