The MAC 35 is probably the least desirable. I have a couple 32's and a 38. I thought they were best left as a saw? Some of the old ones had the carb on the front. Most have needle bearings rather than ball bearings. Some of the latest Macs are much like a Poulan but the 38 is not.

The Craftsman 55 has been a good one to change over. It's much like a Poulan.

The Ryobi has it's following and often converted.