They just reviewed the Savage X and the Hellfire in the latest issue issue of Xtreme RC Cars Magazine the articles should be online in the next few days at www.rc411.com

They do pretty good reviews with dyno data and all that, so that may help you out a bit in your decision. I just picked up the issue today and the Savage X got glowing reviews. They took off a point for not having a 4.6 (.28) engine but said that the 4.1 (.25) was much quicker than the old Savage 25. The Hellfire got a good review with lower marks for durability (weak servo, and soft front A-arms [A-arms were corrected after the first batch of kits and HPI is replacing free of charge for anyone that has the soft ones.]) that seemed to be more of a fluke with the test kit.

Hellfire is a bit pricey and for $650 you get JR Radio gear (a plus IMO) with the LST2. Xtreme RC Cars: LST2 Review

Savage X is about $200 cheaper, and for a first timer that's money well saved on a truck that's pretty durable with lots of hop-ups already available