I have several Dremel tools, the one I reach for most often is my cordless 8220, love it. It's larger than many of the cordless models, but it has power to burn, and the batteries last forever. Not having to deal with the power cord is very nice I have to say. I have two batteries, so one is usually in the charger, and the other in the tool. When You're chewing through diecast with a carbide bit, more power is always handy.
I have a model 4000 as well, it's feature, besides plenty of power, is that it has speed control. For some heavier tasks, this is a handy option.
I honestly don't know how I'd work without the Dremel, I use if for all sorts of tasks.
I do have the flexible wand, the 90 degree cutting head, etc. Although I don't use them often, it's very handy when they're the right fit for the job.
Whatever Dremel model you buy, make sure it has speed control and sufficient power for the job. I still have a little one that I've had for 30 years, I forget the model. It's good for lighter work, but it's not up to some tasks.