In reply to Daniel Hunter:
> a. Do you have to back it up
No but you'd be unwise not to.
> b. Does it ascend smoothly
Yes, very if rigged as per the instructions on a lightly weighted rope.
> c. Any drawbacks/dangers
Not very good for working moves/sequences, you can't easily slide back down a few feet. It can pick at the sheath making your rope furry if you're not careful when moving it down.
> d. Better alternatives
All have strengths and weaknesses. Basic is a pretty good compromise for doing laps on longer routes.
> e. Is there a micro version?
No idea.
jk