What's a good xbox mod chip?

[kitsu]

I'm very new to the whole modding scene, so I was hoping someone could help me out. I wish to mod my xbox, but it seems like there's a lot of different mod chips and I don't want to blow my money on a crappy one. Is there one brand that stands head and shoulders above the rest, or are different chips good for different things?

Also, don't worry about getting the chip installed, I've got enough computer savy friends with the knowledge and tools to help me install it.