Okay, so I've got $270 worth of Discovery Channel Store gift certs burning an e-hole in my e-pocket. I'm trying to decide what to do with them, and have settled on one of two options.

Option 1: Blow them all on the basic DSI package for $299.

Option 2: Get a Variable Telextender, a Pentax K-mount (for my Ricoh SLR), a filter (OIII or narrowband -- haven't decided yet), maybe an eyepiece or two, and a copy of The Elegant Universe on DVD.

I'm mostly interested in the drawbacks and advantages of the DSI v. an SLR camera.

I've come up with these so far:

Drawbacks to the DSI:
Inability to see through the scope to guide it to the target. (I have an LPI now and the most frustrating thing about it is the fact that I have to replace it with an eyepiece, refocus, center the object, replace the LPI, then refocus again.) I realize that with a good alignment and mount this shouldn't be a problem, but small inaccuracies do pop up from time to time.

Benefits to the DSI:
Immediate results.
In the long run, probably cheaper than running to the local Foto-Mart for film processing.

Any suggestions from those of you who have experience with the DSI?