I have had a sar-1 for years and I don't particulary like it. It is reliable and decently accurate but it just seems too cheaply made. It has the canted front sight and may be my least favortie long arm. I have been considering getting a $500+ AK. I love the design just not owning the cheapest one possible.
You could do that with some of the side folders for even less, such as the Romanian for about $40.Looks like a sweet deal. But what's to stop you from buying a $300 sar-1 and slapping a side or under folder on there and being done for under $400?
It's been my experience, underfold stocks for the AK series are a bad idea. The stock is compact, but it doesn't allow a good stock weld and the lock is not as positive as it should be. A side folder, like the Galil or SAKO is much better. Most of the ones I have seen were very loose. I wouldn't want to use one at more than 50 meters.