Is buying a rotary engine a good deal?

for the most part, yes. although they do tend to have a lower fuel economy b/c of the way the chambers rotate

yes, if you’re factoring in coolness into what you consider a, ‘good deal’

It depends on the price. Good deals must include a good price.

I used to own an RX7 with a rotary engine. It was the best vehicle I ever owned. Drove if for years and only put oil and gas into it. The performance was great and the engine was solid and quiet. I wouldn’t hesitate to buy another.