While I have no idea what you are drilling, or intending to drill, I can guess.
I have a 90 degree attachment on my Dremel, and replaced the standard 1/8" collett with a drill type collett that can clamp down on a 1/64" drill bit and even smaller tightly, with no issue.
I pretty much NEVER remove the 90 degree attachement from the dremel, as it allows for so much more precision with just about any tool head I am using, and the tiny drill bits in the tiny drill chuck, well I most recently used it to drill through the solder which remained in the circuit board when I removed a 10K ohm trim pot so I could install wires into a new 5 amp voltage bucker which I use to speed control a 7000 rpm Delta fan.
Seriosuly the 90 degree dremel attachment is So much better, I have only removed it once, and the drill type attachemnt/chuck for the dremel is a thousand times more usedful than the 1/8" inch standard, that I pretty much NEVER remove that either, unless access is dificult as it is a wider diameter.
5k minimum dremel rpm is a lot for a drill but I've had no issues goin through solder, or wood, or fiberglass, or PLA, or carbon fiber with it.
