oh i scoff at the rst! i like the way that someone else on the forum put it- "the rst no-travel fork" my stepdad just bought a bike for my mom with the rst and i think the acera, which is good for her because she won't be using it as an actual "mountain bike". sorry to dicourage but this is the way i feel. when i bought my first REAL bike which was my last one, it was a trek 4900 with the judytt fork and shimano deore- the other choice was a manitou fork which was $50 cheaper i was very pleased with my choice even to the day i sold it. it would have been silly for me to buy a full suspension as my first bike because i wouldn't have appreciated it nearly as much which is why it's good to get just the basics for your first bike- but you should still get quality if you can afford to. i sold my trek to my step dad so i can still see my first love when i want, and compared to my moms bike, let's just say my mom's bike is put to absolute shame. yes your bike should hold up but you will soon realize that you need performance whick the rst does not have. As for the derailer like i said, i got the deore which i had no problems with but people (a person?) here said that deore suscks.
i'm pretty sure that deore is better quality than acera but in reality i doubt any beginer would really see the differnce so probably not too bad of a choice but at the same time i think that if you just go and buy the cheapest bike at the bike shop, you just might as well go buy one at target- this may be an exaggeration. my general rule of thumb is if you want to get a good, descent, solid bike, you should plan on spending about $500.i would just hope that you aren't held back from seeing an awsome sport because of your equipment. what kind of riding to you plan on doing? i think you will enjoy anyway.