Asking if a Saiga is a good rifle is like asking if a Ferrari is a reasonably fast car. Yes, they are, but there are two basic types, one more desirable than the other. Both are genuine Russian rifles made at the Izhevsk Plant with the first type being the sporter version which has been very modified at the factory to lose all the evil features. They look like a cross between an AK and a semi-auto hunting rifle. They can be backward modified to their original glory, but you'll have a few extra holes in the receiver where the trigger group was moved from. You'll also have to install a bullet guide, change the gas block and install a new FSB, to name a few things. Some companies sell a semi-converted version where some of these things have already been done.
The other Saiga's are the Legions. They are civilian versions of the AK-100 series of rifles. These are much more desirable. Unfortunately, all types of Saigas have been banned from further importation by our President. As with anything no longer obtainable, the value of these rifles has increased quite a bit recently. When I got my first Legion, I paid $500. The next one cost me $800. Now, you can't touch them for under $1000. Most of the Legions are hovering around $1500 and the Sporters are in the $600+ range.
Uncoverted Siaga Sporter. Notice the location of the trigger and trigger guard in relation to the magazine, then compare it to the next Saiga.
Partially converted Saiga Sporter. These are done here after being imported as Sporters.
My two Legions, one in 7.62x39, the other in 5.45x39.