I'd say yes, go for it, if you have room and time to work on them. They're fun, reliable and cheap for an M. What else are you going to get for under $15k that can do what this car does, at least within the BMW family?
Mine gets the least used out of all my cars, but I enjoy taking it out on drives. Makes my E92 M3 feel like a 5 series in terms of size and insulation. I wouldn't call the engine super special, but at the same time, it's still a great inline 6 made from BMW, so since when is that a bad thing? Consumables are pretty damn cheap compared to anything after that, but the plastics/interior/exterior doesn't wear that well.
Here's mine:
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Current:
16 F82 M4 GTS, Black Sapphire/Black, DCT
08 E92 M3, Sparkling Graphite/Bamboo Beige, 6MT
07 E85 Z4M Roadster, Alpine White/Red, 6MT
99 E36 M3, Techno Violet/Dove Grey, 6MT