well, i wont say if one is better than the other. these two programs couldnt be more different.
Cubase is amazing, i love it despite all its glitches and faults.
But it took me the better part of 3 years to move inside it with confidence.
Another thing to consider is that whilst the price difference is quite small, Reason is a ready made environment, with fixed generators and effects.
Cubase is a host.
What this means, is that if you have reason, your only worry will be gathering samples, and learning how to make the most out of each unit.
With cubase, sonar, logic, reaper etc, its a never-ending pursuit of getting the newest plug in or synth that the market has hyped as the next best thing after oral sex. and trust me, this is a vicious circle that many self taught producers have fallen into, with most common result despair and frustration, and ultimately, surrender.
Many think that reason's inability to host third party plug ins is a downfall. i think that having a limited amount of tools pushes you into using them to their limits, and also stops you from becoming a gearslut...
dont wanna patronise you, but if i guess correctly you're just starting your venture in music making.
If that's the case, then id suggest you buy Reason, and a good editing program, eg Wavelab or Soundforge. The purpose of the latter is to allow you to chop/trim samples in audio, just like you'd do in cubase.
Theres tons of acclaimed producers that use just that combination.
Limewax, Cooh, Nu Tone, Logistics. list is bloody endless. i read sumthin bout Liam from prodigy using it loads too, but i have my doubts...
hope this helps a bit, and just like everything else you read in production forums, dont take this advice as a holy book, but rather a starting point for your own research.